feat(reject-history): multi-pareto 3×2 grid with cross-filter linkage

Replace single-dimension Pareto dropdown with 6 simultaneous Pareto charts (不良原因, PACKAGE, TYPE, WORKFLOW, 站點, 機台) in a responsive 3-column grid. Clicking items in one Pareto cross-filters the other 5 (exclude-self logic), and the detail table applies all dimension selections with AND logic. Backend: - Add batch-pareto endpoint (cache-only, no Oracle queries) - Add _apply_cross_filter() with exclude-self pattern - Extend view/export endpoints for multi-dimension sel_* params Frontend: - New ParetoGrid.vue wrapping 6 ParetoSection instances - Simplify ParetoSection: remove dimension dropdown, keep TOP20 toggle - Replace single-dimension state with paretoSelections reactive object - Adaptive x-axis labels (font size, rotation, hideOverlap) for compact grid - Responsive grid: 3-col desktop, 2-col tablet, 1-col mobile Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-03-02 14:43:35 +08:00
parent e83d8e1a36
commit 2568fd836c
20 changed files with 1558 additions and 534 deletions
--- a/frontend/src/core/reject-history-filters.js
+++ b/frontend/src/core/reject-history-filters.js
@@ -173,8 +173,7 @@ export function buildViewParams(queryId, {
  metricFilter = 'all',
  trendDates = [],
  detailReason = '',
-  paretoDimension = '',
-  paretoValues = [],
+  paretoSelections = {},
  page = 1,
  perPage = 50,
  policyFilters = {},
@@ -198,13 +197,19 @@ export function buildViewParams(queryId, {
  if (detailReason) {
    params.detail_reason = detailReason;
  }
-  const normalizedParetoDimension = normalizeText(paretoDimension).toLowerCase();
-  const normalizedParetoValues = normalizeArray(paretoValues);
-  if (normalizedParetoDimension) {
-    params.pareto_dimension = normalizedParetoDimension;
+  const selectionParamMap = {
+    reason: 'sel_reason',
+    package: 'sel_package',
+    type: 'sel_type',
+    workflow: 'sel_workflow',
+    workcenter: 'sel_workcenter',
+    equipment: 'sel_equipment',
+  };
+  for (const [dimension, paramName] of Object.entries(selectionParamMap)) {
+    const normalizedValues = normalizeArray(paretoSelections?.[dimension]);
+    if (normalizedValues.length > 0) {
+      params[paramName] = normalizedValues;
    }
-  if (normalizedParetoValues.length > 0) {
-    params.pareto_values = normalizedParetoValues;
  }
  params.page = page || 1;
  params.per_page = perPage || 50;
--- a/frontend/src/reject-history/App.vue
+++ b/frontend/src/reject-history/App.vue
@@ -10,22 +10,64 @@ import { replaceRuntimeHistory } from '../core/shell-navigation.js';

 import DetailTable from './components/DetailTable.vue';
 import FilterPanel from './components/FilterPanel.vue';
-import ParetoSection from './components/ParetoSection.vue';
+import ParetoGrid from './components/ParetoGrid.vue';
 import SummaryCards from './components/SummaryCards.vue';
 import TrendChart from './components/TrendChart.vue';

 const API_TIMEOUT = 360000;
 const DEFAULT_PER_PAGE = 50;
 const PARETO_TOP20_DIMENSIONS = new Set(['type', 'workflow', 'equipment']);
-const PARETO_DIMENSION_LABELS = {
-  reason: '不良原因',
-  package: 'PACKAGE',
-  type: 'TYPE',
-  workflow: 'WORKFLOW',
-  workcenter: '站點',
-  equipment: '機台',
+const PARETO_DIMENSIONS = ['reason', 'package', 'type', 'workflow', 'workcenter', 'equipment'];
+const PARETO_SELECTION_PARAM_MAP = {
+  reason: 'sel_reason',
+  package: 'sel_package',
+  type: 'sel_type',
+  workflow: 'sel_workflow',
+  workcenter: 'sel_workcenter',
+  equipment: 'sel_equipment',
 };

+function createEmptyParetoSelections() {
+  return {
+    reason: [],
+    package: [],
+    type: [],
+    workflow: [],
+    workcenter: [],
+    equipment: [],
+  };
+}
+
+function createEmptyParetoData() {
+  return {
+    reason: { items: [], dimension: 'reason', metric_mode: 'reject_total' },
+    package: { items: [], dimension: 'package', metric_mode: 'reject_total' },
+    type: { items: [], dimension: 'type', metric_mode: 'reject_total' },
+    workflow: { items: [], dimension: 'workflow', metric_mode: 'reject_total' },
+    workcenter: { items: [], dimension: 'workcenter', metric_mode: 'reject_total' },
+    equipment: { items: [], dimension: 'equipment', metric_mode: 'reject_total' },
+  };
+}
+
+function getDimensionLabel(dimension) {
+  switch (dimension) {
+    case 'reason':
+      return '不良原因';
+    case 'package':
+      return 'PACKAGE';
+    case 'type':
+      return 'TYPE';
+    case 'workflow':
+      return 'WORKFLOW';
+    case 'workcenter':
+      return '站點';
+    case 'equipment':
+      return '機台';
+    default:
+      return 'Pareto';
+  }
+}
+
 // ---- Primary query form state ----
 const queryMode = ref('date_range');
 const containerInputType = ref('lot');
@@ -69,11 +111,9 @@ const supplementaryFilters = reactive({
 const page = ref(1);
 const selectedTrendDates = ref([]);
 const trendLegendSelected = ref({ '扣帳報廢量': true, '不扣帳報廢量': true });
-const paretoDimension = ref('reason');
-const selectedParetoValues = ref([]);
 const paretoDisplayScope = ref('all');
-const dimensionParetoItems = ref([]);
-const dimensionParetoLoading = ref(false);
+const paretoSelections = reactive(createEmptyParetoSelections());
+const paretoData = reactive(createEmptyParetoData());

 // ---- Data state ----
 const summary = ref({
@@ -102,6 +142,7 @@ const loading = reactive({
  initial: false,
  querying: false,
  list: false,
+  pareto: false,
  exporting: false,
 });
 const errorMessage = ref('');
@@ -109,6 +150,7 @@ const lastQueryAt = ref('');

 // ---- Request staleness tracking ----
 let activeRequestId = 0;
+let activeParetoRequestId = 0;

 function nextRequestId() {
  activeRequestId += 1;
@@ -119,6 +161,15 @@ function isStaleRequest(id) {
  return id !== activeRequestId;
 }

+function nextParetoRequestId() {
+  activeParetoRequestId += 1;
+  return activeParetoRequestId;
+}
+
+function isStaleParetoRequest(id) {
+  return id !== activeParetoRequestId;
+}
+
 // ---- Helpers ----
 function toDateString(value) {
  const y = value.getFullYear();
@@ -143,6 +194,10 @@ function metricFilterParam() {
  return 'all';
 }

+function paretoMetricApiMode() {
+  return paretoMetricMode.value === 'defect' ? 'defect' : 'reject_total';
+}
+
 function unwrapApiResult(result, fallbackMessage) {
  if (result?.success === true) {
    return result;
@@ -153,6 +208,93 @@ function unwrapApiResult(result, fallbackMessage) {
  return result;
 }

+function resetParetoSelections() {
+  for (const dimension of PARETO_DIMENSIONS) {
+    paretoSelections[dimension] = [];
+  }
+}
+
+function resetParetoData() {
+  for (const dimension of PARETO_DIMENSIONS) {
+    paretoData[dimension] = {
+      items: [],
+      dimension,
+      metric_mode: paretoMetricApiMode(),
+    };
+  }
+}
+
+function buildBatchParetoParams() {
+  const params = {
+    query_id: queryId.value,
+    metric_mode: paretoMetricApiMode(),
+    pareto_scope: committedPrimary.paretoTop80 ? 'top80' : 'all',
+    pareto_display_scope: paretoDisplayScope.value,
+    include_excluded_scrap: committedPrimary.includeExcludedScrap ? 'true' : 'false',
+    exclude_material_scrap: committedPrimary.excludeMaterialScrap ? 'true' : 'false',
+    exclude_pb_diode: committedPrimary.excludePbDiode ? 'true' : 'false',
+  };
+
+  if (supplementaryFilters.packages.length > 0) {
+    params.packages = supplementaryFilters.packages;
+  }
+  if (supplementaryFilters.workcenterGroups.length > 0) {
+    params.workcenter_groups = supplementaryFilters.workcenterGroups;
+  }
+  if (supplementaryFilters.reason) {
+    params.reason = supplementaryFilters.reason;
+  }
+  if (selectedTrendDates.value.length > 0) {
+    params.trend_dates = selectedTrendDates.value;
+  }
+  for (const [dimension, key] of Object.entries(PARETO_SELECTION_PARAM_MAP)) {
+    if (paretoSelections[dimension]?.length > 0) {
+      params[key] = paretoSelections[dimension];
+    }
+  }
+  return params;
+}
+
+async function fetchBatchPareto() {
+  if (!queryId.value) return;
+
+  const requestId = nextParetoRequestId();
+  loading.pareto = true;
+
+  try {
+    const resp = await apiGet('/api/reject-history/batch-pareto', {
+      params: buildBatchParetoParams(),
+      timeout: API_TIMEOUT,
+    });
+    if (isStaleParetoRequest(requestId)) return;
+
+    if (resp?.success === false && resp?.error === 'cache_miss') {
+      await executePrimaryQuery();
+      return;
+    }
+
+    const result = unwrapApiResult(resp, '查詢批次 Pareto 失敗');
+    const dimensions = result.data?.dimensions || {};
+    for (const dimension of PARETO_DIMENSIONS) {
+      paretoData[dimension] = dimensions[dimension] || {
+        items: [],
+        dimension,
+        metric_mode: paretoMetricApiMode(),
+      };
+    }
+  } catch (error) {
+    if (isStaleParetoRequest(requestId)) return;
+    resetParetoData();
+    if (error?.name !== 'AbortError') {
+      errorMessage.value = error?.message || '查詢批次 Pareto 失敗';
+    }
+  } finally {
+    if (!isStaleParetoRequest(requestId)) {
+      loading.pareto = false;
+    }
+  }
+}
+
 // ---- Primary query (POST /query → Oracle → cache) ----
 async function executePrimaryQuery() {
  const requestId = nextRequestId();
@@ -180,7 +322,6 @@ async function executePrimaryQuery() {

    const result = unwrapApiResult(resp, '主查詢執行失敗');

-    // Commit primary params for URL state and chips
    committedPrimary.mode = queryMode.value;
    committedPrimary.startDate = draftFilters.startDate;
    committedPrimary.endDate = draftFilters.endDate;
@@ -192,7 +333,6 @@ async function executePrimaryQuery() {
    committedPrimary.excludePbDiode = draftFilters.excludePbDiode;
    committedPrimary.paretoTop80 = draftFilters.paretoTop80;

-    // Store query result
    queryId.value = result.query_id;
    resolutionInfo.value = result.resolution_info || null;
    const af = result.available_filters || {};
@@ -202,24 +342,22 @@ async function executePrimaryQuery() {
      reasons: af.reasons || [],
    };

-    // Reset supplementary + interactive
    supplementaryFilters.packages = [];
    supplementaryFilters.workcenterGroups = [];
    supplementaryFilters.reason = '';
    page.value = 1;
    selectedTrendDates.value = [];
-    selectedParetoValues.value = [];
-    paretoDisplayScope.value = 'all';
-    paretoDimension.value = 'reason';
-    dimensionParetoItems.value = [];
+    resetParetoSelections();
+    resetParetoData();

-    // Apply initial data
    analyticsRawItems.value = Array.isArray(result.analytics_raw)
      ? result.analytics_raw
      : [];
    summary.value = result.summary || summary.value;
    detail.value = result.detail || detail.value;

+    await fetchBatchPareto();
+
    lastQueryAt.value = new Date().toLocaleString('zh-TW');
    updateUrlState();
  } catch (error) {
@@ -249,8 +387,7 @@ async function refreshView() {
      supplementaryFilters,
      metricFilter: metricFilterParam(),
      trendDates: selectedTrendDates.value,
-      paretoDimension: paretoDimension.value,
-      paretoValues: selectedParetoValues.value,
+      paretoSelections,
      page: page.value,
      perPage: DEFAULT_PER_PAGE,
      policyFilters: {
@@ -266,7 +403,6 @@ async function refreshView() {
    });
    if (isStaleRequest(requestId)) return;

-    // Handle cache expired → auto re-execute primary query
    if (resp?.success === false && resp?.error === 'cache_expired') {
      await executePrimaryQuery();
      return;
@@ -309,6 +445,8 @@ function clearFilters() {
  draftFilters.excludeMaterialScrap = true;
  draftFilters.excludePbDiode = true;
  draftFilters.paretoTop80 = true;
+  paretoDisplayScope.value = 'all';
+  resetParetoSelections();
  void executePrimaryQuery();
 }

@@ -329,110 +467,54 @@ function onTrendDateClick(dateStr) {
    selectedTrendDates.value = [...selectedTrendDates.value, dateStr];
  }
  page.value = 1;
-  void refreshView();
-  refreshDimensionParetoIfActive();
+  updateUrlState();
+  void Promise.all([refreshView(), fetchBatchPareto()]);
 }

 function onTrendLegendChange(selected) {
  trendLegendSelected.value = { ...selected };
  page.value = 1;
  updateUrlState();
-  void refreshView();
-  refreshDimensionParetoIfActive();
+  void Promise.all([refreshView(), fetchBatchPareto()]);
 }

-function onParetoItemToggle(itemValue) {
+function onParetoItemToggle(dimension, itemValue) {
+  if (!Object.hasOwn(PARETO_SELECTION_PARAM_MAP, dimension)) {
+    return;
+  }
  const normalized = String(itemValue || '').trim();
  if (!normalized) return;
-  if (selectedParetoValues.value.includes(normalized)) {
-    selectedParetoValues.value = selectedParetoValues.value.filter(
-      (item) => item !== normalized,
-    );
+
+  const current = paretoSelections[dimension] || [];
+  if (current.includes(normalized)) {
+    paretoSelections[dimension] = current.filter((item) => item !== normalized);
  } else {
-    selectedParetoValues.value = [...selectedParetoValues.value, normalized];
+    paretoSelections[dimension] = [...current, normalized];
  }
+
  page.value = 1;
  updateUrlState();
-  void refreshView();
+  void Promise.all([fetchBatchPareto(), refreshView()]);
 }

 function handleParetoScopeToggle(checked) {
  draftFilters.paretoTop80 = Boolean(checked);
  committedPrimary.paretoTop80 = Boolean(checked);
  updateUrlState();
-  refreshDimensionParetoIfActive();
-}
-
-let activeDimRequestId = 0;
-
-async function fetchDimensionPareto(dim) {
-  if (dim === 'reason' || !queryId.value) return;
-  activeDimRequestId += 1;
-  const myId = activeDimRequestId;
-  dimensionParetoLoading.value = true;
-  try {
-    const params = {
-      query_id: queryId.value,
-      start_date: committedPrimary.startDate,
-      end_date: committedPrimary.endDate,
-      dimension: dim,
-      metric_mode: paretoMetricMode.value === 'defect' ? 'defect' : 'reject_total',
-      pareto_scope: committedPrimary.paretoTop80 ? 'top80' : 'all',
-      include_excluded_scrap: committedPrimary.includeExcludedScrap,
-      exclude_material_scrap: committedPrimary.excludeMaterialScrap,
-      exclude_pb_diode: committedPrimary.excludePbDiode,
-      packages: supplementaryFilters.packages.length > 0 ? supplementaryFilters.packages : undefined,
-      workcenter_groups: supplementaryFilters.workcenterGroups.length > 0 ? supplementaryFilters.workcenterGroups : undefined,
-      reason: supplementaryFilters.reason || undefined,
-      trend_dates: selectedTrendDates.value.length > 0 ? selectedTrendDates.value : undefined,
-    };
-    const resp = await apiGet('/api/reject-history/reason-pareto', { params, timeout: API_TIMEOUT });
-    if (myId !== activeDimRequestId) return;
-    const result = unwrapApiResult(resp, '查詢維度 Pareto 失敗');
-    dimensionParetoItems.value = result.data?.items || [];
-  } catch (err) {
-    if (myId !== activeDimRequestId) return;
-    dimensionParetoItems.value = [];
-    if (err?.name !== 'AbortError') {
-      errorMessage.value = err.message || '查詢維度 Pareto 失敗';
-    }
-  } finally {
-    if (myId === activeDimRequestId) {
-      dimensionParetoLoading.value = false;
-    }
-  }
-}
-
-function refreshDimensionParetoIfActive() {
-  if (paretoDimension.value !== 'reason') {
-    void fetchDimensionPareto(paretoDimension.value);
-  }
-}
-
-function onDimensionChange(dim) {
-  paretoDimension.value = dim;
-  selectedParetoValues.value = [];
-  paretoDisplayScope.value = 'all';
-  page.value = 1;
-  if (dim === 'reason') {
-    dimensionParetoItems.value = [];
-    void refreshView();
-  } else {
-    void fetchDimensionPareto(dim);
-    void refreshView();
-  }
+  void fetchBatchPareto();
 }

 function onParetoDisplayScopeChange(scope) {
  paretoDisplayScope.value = scope === 'top20' ? 'top20' : 'all';
  updateUrlState();
+  void fetchBatchPareto();
 }

 function clearParetoSelection() {
-  selectedParetoValues.value = [];
+  resetParetoSelections();
  page.value = 1;
  updateUrlState();
-  void refreshView();
+  void Promise.all([fetchBatchPareto(), refreshView()]);
 }

 function onSupplementaryChange(filters) {
@@ -441,37 +523,32 @@ function onSupplementaryChange(filters) {
  supplementaryFilters.reason = filters.reason || '';
  page.value = 1;
  selectedTrendDates.value = [];
-  selectedParetoValues.value = [];
-  void refreshView();
-  refreshDimensionParetoIfActive();
+  resetParetoSelections();
+  updateUrlState();
+  void Promise.all([refreshView(), fetchBatchPareto()]);
 }

 function removeFilterChip(chip) {
  if (!chip?.removable) return;

  if (chip.type === 'pareto-value') {
-    selectedParetoValues.value = selectedParetoValues.value.filter(
-      (value) => value !== chip.value,
-    );
-    page.value = 1;
-    updateUrlState();
-    void refreshView();
+    onParetoItemToggle(chip.dimension, chip.value);
    return;
  }

  if (chip.type === 'trend-dates') {
    selectedTrendDates.value = [];
    page.value = 1;
-    void refreshView();
-    refreshDimensionParetoIfActive();
+    updateUrlState();
+    void Promise.all([refreshView(), fetchBatchPareto()]);
    return;
  }

  if (chip.type === 'reason') {
    supplementaryFilters.reason = '';
    page.value = 1;
-    void refreshView();
-    refreshDimensionParetoIfActive();
+    updateUrlState();
+    void Promise.all([refreshView(), fetchBatchPareto()]);
    return;
  }

@@ -480,8 +557,8 @@ function removeFilterChip(chip) {
      (g) => g !== chip.value,
    );
    page.value = 1;
-    void refreshView();
-    refreshDimensionParetoIfActive();
+    updateUrlState();
+    void Promise.all([refreshView(), fetchBatchPareto()]);
    return;
  }

@@ -490,9 +567,8 @@ function removeFilterChip(chip) {
      (p) => p !== chip.value,
    );
    page.value = 1;
-    void refreshView();
-    refreshDimensionParetoIfActive();
-    return;
+    updateUrlState();
+    void Promise.all([refreshView(), fetchBatchPareto()]);
  }
 }

@@ -511,10 +587,12 @@ async function exportCsv() {
    if (supplementaryFilters.reason) params.set('reason', supplementaryFilters.reason);
    params.set('metric_filter', metricFilterParam());
    for (const date of selectedTrendDates.value) params.append('trend_dates', date);
-    params.set('pareto_dimension', paretoDimension.value);
-    for (const value of selectedParetoValues.value) params.append('pareto_values', value);
+    for (const [dimension, key] of Object.entries(PARETO_SELECTION_PARAM_MAP)) {
+      for (const value of paretoSelections[dimension] || []) {
+        params.append(key, value);
+      }
+    }

-    // Policy filters (applied in-memory on cached data)
    if (committedPrimary.includeExcludedScrap) params.set('include_excluded_scrap', 'true');
    if (!committedPrimary.excludeMaterialScrap) params.set('exclude_material_scrap', 'false');
    if (!committedPrimary.excludePbDiode) params.set('exclude_pb_diode', 'false');
@@ -612,99 +690,30 @@ const paretoMetricLabel = computed(() => {
  }
 });

-const allParetoItems = computed(() => {
-  const raw = analyticsRawItems.value;
-  if (!raw || raw.length === 0) return [];
-
-  const mode = paretoMetricMode.value;
-  if (mode === 'none') return [];
-
-  const dateSet =
-    selectedTrendDates.value.length > 0 ? new Set(selectedTrendDates.value) : null;
-  const filtered = dateSet ? raw.filter((r) => dateSet.has(r.bucket_date)) : raw;
-  if (filtered.length === 0) return [];
-
-  const map = new Map();
-  for (const item of filtered) {
-    const key = item.reason;
-    if (!map.has(key)) {
-      map.set(key, {
-        reason: key,
-        MOVEIN_QTY: 0,
-        REJECT_TOTAL_QTY: 0,
-        DEFECT_QTY: 0,
-        AFFECTED_LOT_COUNT: 0,
-      });
+const selectedParetoCount = computed(() => {
+  let count = 0;
+  for (const dimension of PARETO_DIMENSIONS) {
+    count += (paretoSelections[dimension] || []).length;
  }
-    const acc = map.get(key);
-    acc.MOVEIN_QTY += Number(item.MOVEIN_QTY || 0);
-    acc.REJECT_TOTAL_QTY += Number(item.REJECT_TOTAL_QTY || 0);
-    acc.DEFECT_QTY += Number(item.DEFECT_QTY || 0);
-    acc.AFFECTED_LOT_COUNT += Number(item.AFFECTED_LOT_COUNT || 0);
-  }
-
-  const withMetric = Array.from(map.values()).map((row) => {
-    let mv;
-    if (mode === 'all') mv = row.REJECT_TOTAL_QTY + row.DEFECT_QTY;
-    else if (mode === 'reject') mv = row.REJECT_TOTAL_QTY;
-    else mv = row.DEFECT_QTY;
-    return { ...row, metric_value: mv };
-  });
-
-  const sorted = withMetric
-    .filter((r) => r.metric_value > 0)
-    .sort((a, b) => b.metric_value - a.metric_value);
-  const total = sorted.reduce((sum, r) => sum + r.metric_value, 0);
-  let cum = 0;
-  return sorted.map((row) => {
-    const pct = total ? Number(((row.metric_value / total) * 100).toFixed(4)) : 0;
-    cum += pct;
-    return {
-      reason: row.reason,
-      metric_value: row.metric_value,
-      MOVEIN_QTY: row.MOVEIN_QTY,
-      REJECT_TOTAL_QTY: row.REJECT_TOTAL_QTY,
-      DEFECT_QTY: row.DEFECT_QTY,
-      count: row.AFFECTED_LOT_COUNT,
-      pct,
-      cumPct: Number(cum.toFixed(4)),
-    };
-  });
+  return count;
 });

-const filteredParetoItems = computed(() => {
-  const items = allParetoItems.value || [];
-  if (!committedPrimary.paretoTop80 || items.length === 0) {
-    return items;
+const selectedParetoSummary = computed(() => {
+  const tokens = [];
+  for (const dimension of PARETO_DIMENSIONS) {
+    for (const value of paretoSelections[dimension] || []) {
+      tokens.push(`${getDimensionLabel(dimension)}:${value}`);
    }
-  const cutIdx = items.findIndex((item) => Number(item.cumPct || 0) >= 80);
-  const top80Count = cutIdx >= 0 ? cutIdx + 1 : items.length;
-  return items.slice(0, Math.max(top80Count, Math.min(5, items.length)));
-});
-
-const activeParetoItems = computed(() => {
-  const baseItems =
-    paretoDimension.value === 'reason'
-      ? filteredParetoItems.value
-      : (dimensionParetoItems.value || []);
-
-  if (
-    PARETO_TOP20_DIMENSIONS.has(paretoDimension.value)
-    && paretoDisplayScope.value === 'top20'
-  ) {
-    return baseItems.slice(0, 20);
  }
-  return baseItems;
+  if (tokens.length <= 3) {
+    return tokens.join(', ');
+  }
+  return `${tokens.slice(0, 3).join(', ')}... (${tokens.length} 項)`;
 });

-const selectedParetoDimensionLabel = computed(
-  () => PARETO_DIMENSION_LABELS[paretoDimension.value] || 'Pareto',
-);
-
 const activeFilterChips = computed(() => {
  const chips = [];

-  // Primary query info
  if (committedPrimary.mode === 'date_range') {
    chips.push({
      key: 'date-range',
@@ -727,7 +736,6 @@ const activeFilterChips = computed(() => {
    });
  }

-  // Policy chips
  chips.push({
    key: 'policy-mode',
    label: committedPrimary.includeExcludedScrap
@@ -752,7 +760,6 @@ const activeFilterChips = computed(() => {
    value: '',
  });

-  // Supplementary chips (removable)
  if (supplementaryFilters.reason) {
    chips.push({
      key: `reason:${supplementaryFilters.reason}`,
@@ -783,7 +790,6 @@ const activeFilterChips = computed(() => {
    });
  });

-  // Interactive chips (removable)
  if (selectedTrendDates.value.length > 0) {
    const dates = selectedTrendDates.value;
    const label =
@@ -797,15 +803,18 @@ const activeFilterChips = computed(() => {
    });
  }

-  selectedParetoValues.value.forEach((value) => {
+  for (const dimension of PARETO_DIMENSIONS) {
+    for (const value of paretoSelections[dimension] || []) {
      chips.push({
-      key: `pareto-value:${paretoDimension.value}:${value}`,
-      label: `${selectedParetoDimensionLabel.value}: ${value}`,
+        key: `pareto-value:${dimension}:${value}`,
+        label: `${getDimensionLabel(dimension)}: ${value}`,
        removable: true,
        type: 'pareto-value',
+        dimension,
        value,
      });
-  });
+    }
+  }

  return chips;
 });
@@ -855,18 +864,20 @@ function updateUrlState() {
  params.set('exclude_material_scrap', String(committedPrimary.excludeMaterialScrap));
  params.set('exclude_pb_diode', String(committedPrimary.excludePbDiode));

-  // Supplementary
  appendArrayParams(params, 'packages', supplementaryFilters.packages);
  appendArrayParams(params, 'workcenter_groups', supplementaryFilters.workcenterGroups);
  if (supplementaryFilters.reason) {
    params.set('reason', supplementaryFilters.reason);
  }

-  // Interactive
  appendArrayParams(params, 'trend_dates', selectedTrendDates.value);
-  params.set('pareto_dimension', paretoDimension.value);
-  appendArrayParams(params, 'pareto_values', selectedParetoValues.value);
-  if (paretoDisplayScope.value !== 'all') params.set('pareto_display_scope', paretoDisplayScope.value);
+  for (const [dimension, key] of Object.entries(PARETO_SELECTION_PARAM_MAP)) {
+    appendArrayParams(params, key, paretoSelections[dimension] || []);
+  }
+
+  if (paretoDisplayScope.value !== 'all') {
+    params.set('pareto_display_scope', paretoDisplayScope.value);
+  }
  if (!committedPrimary.paretoTop80) {
    params.set('pareto_scope_all', 'true');
  }
@@ -903,7 +914,6 @@ function readBooleanParam(params, key, defaultValue = false) {
 function restoreFromUrl() {
  const params = new URLSearchParams(window.location.search);

-  // Mode
  const mode = String(params.get('mode') || '').trim();
  if (mode === 'container') {
    queryMode.value = 'container';
@@ -920,7 +930,6 @@ function restoreFromUrl() {
    }
  }

-  // Policy
  draftFilters.includeExcludedScrap = readBooleanParam(
    params,
    'include_excluded_scrap',
@@ -934,38 +943,38 @@ function restoreFromUrl() {
  draftFilters.excludePbDiode = readBooleanParam(params, 'exclude_pb_diode', true);
  draftFilters.paretoTop80 = !readBooleanParam(params, 'pareto_scope_all', false);

-  // Supplementary (will be applied after primary query)
-  const urlPackages = readArrayParam(params, 'packages');
-  const urlWcGroups = readArrayParam(params, 'workcenter_groups');
-  const urlReason = String(params.get('reason') || '').trim();
+  supplementaryFilters.packages = readArrayParam(params, 'packages');
+  supplementaryFilters.workcenterGroups = readArrayParam(params, 'workcenter_groups');
+  supplementaryFilters.reason = String(params.get('reason') || '').trim();

-  // Interactive
-  const urlTrendDates = readArrayParam(params, 'trend_dates');
-  const rawParetoDimension = String(params.get('pareto_dimension') || '').trim().toLowerCase();
-  const urlParetoDimension = Object.hasOwn(PARETO_DIMENSION_LABELS, rawParetoDimension)
-    ? rawParetoDimension
+  selectedTrendDates.value = readArrayParam(params, 'trend_dates');
+
+  const restoredSelections = createEmptyParetoSelections();
+  for (const [dimension, key] of Object.entries(PARETO_SELECTION_PARAM_MAP)) {
+    restoredSelections[dimension] = readArrayParam(params, key);
+  }
+
+  const legacyDimension = String(params.get('pareto_dimension') || '').trim().toLowerCase();
+  const legacyValues = readArrayParam(params, 'pareto_values');
+  const hasSelParams = Object.values(restoredSelections).some((values) => values.length > 0);
+  if (!hasSelParams && legacyValues.length > 0) {
+    const fallbackDimension = Object.hasOwn(PARETO_SELECTION_PARAM_MAP, legacyDimension)
+      ? legacyDimension
      : 'reason';
-  const urlParetoValues = readArrayParam(params, 'pareto_values');
-  const urlParetoDisplayScope = String(params.get('pareto_display_scope') || '').trim().toLowerCase();
-  const parsedPage = Number(params.get('page') || '1');
+    restoredSelections[fallbackDimension] = legacyValues;
+  }

-  paretoDimension.value = urlParetoDimension;
-  selectedParetoValues.value = urlParetoValues;
+  for (const dimension of PARETO_DIMENSIONS) {
+    paretoSelections[dimension] = restoredSelections[dimension];
+  }
+
+  const urlParetoDisplayScope = String(params.get('pareto_display_scope') || '').trim().toLowerCase();
  paretoDisplayScope.value = urlParetoDisplayScope === 'top20' ? 'top20' : 'all';

-  return {
-    packages: urlPackages,
-    workcenterGroups: urlWcGroups,
-    reason: urlReason,
-    trendDates: urlTrendDates,
-    paretoDimension: urlParetoDimension,
-    paretoValues: urlParetoValues,
-    paretoDisplayScope: paretoDisplayScope.value,
-    page: Number.isFinite(parsedPage) && parsedPage > 0 ? parsedPage : 1,
-  };
+  const parsedPage = Number(params.get('page') || '1');
+  page.value = Number.isFinite(parsedPage) && parsedPage > 0 ? parsedPage : 1;
 }

-// ---- Mount ----
 onMounted(() => {
  setDefaultDateRange();
  restoreFromUrl();
@@ -1004,11 +1013,13 @@ onMounted(() => {
      :resolution-info="resolutionInfo"
      :loading="loading"
      :active-filter-chips="activeFilterChips"
+      :pareto-display-scope="paretoDisplayScope"
      @apply="applyFilters"
      @clear="clearFilters"
      @export-csv="exportCsv"
      @remove-chip="removeFilterChip"
      @pareto-scope-toggle="handleParetoScopeToggle"
+      @pareto-display-scope-change="onParetoDisplayScopeChange"
      @update:query-mode="queryMode = $event"
      @update:container-input-type="containerInputType = $event"
      @update:container-input="containerInput = $event"
@@ -1026,26 +1037,22 @@ onMounted(() => {
        @legend-change="onTrendLegendChange"
      />

-      <ParetoSection
-        :items="activeParetoItems"
-        :selected-values="selectedParetoValues"
+      <ParetoGrid
+        :pareto-data="paretoData"
+        :pareto-selections="paretoSelections"
        :display-scope="paretoDisplayScope"
        :selected-dates="selectedTrendDates"
        :metric-label="paretoMetricLabel"
-        :loading="loading.querying || dimensionParetoLoading"
-        :dimension="paretoDimension"
-        :show-dimension-selector="committedPrimary.mode === 'date_range'"
+        :loading="loading.querying || loading.pareto"
        @item-toggle="onParetoItemToggle"
-        @dimension-change="onDimensionChange"
-        @display-scope-change="onParetoDisplayScopeChange"
      />

      <DetailTable
        :items="detail.items"
        :pagination="pagination"
        :loading="loading.list"
-        :selected-pareto-values="selectedParetoValues"
-        :selected-pareto-dimension-label="selectedParetoDimensionLabel"
+        :selected-pareto-count="selectedParetoCount"
+        :selected-pareto-summary="selectedParetoSummary"
        @go-to-page="goToPage"
        @clear-pareto-selection="clearParetoSelection"
      />
--- a/frontend/src/reject-history/components/DetailTable.vue
+++ b/frontend/src/reject-history/components/DetailTable.vue
@@ -8,8 +8,8 @@ defineProps({
    default: () => ({ page: 1, perPage: 50, total: 0, totalPages: 1 }),
  },
  loading: { type: Boolean, default: false },
-  selectedParetoValues: { type: Array, default: () => [] },
-  selectedParetoDimensionLabel: { type: String, default: '' },
+  selectedParetoCount: { type: Number, default: 0 },
+  selectedParetoSummary: { type: String, default: '' },
 });

 defineEmits(['go-to-page', 'clear-pareto-selection']);
@@ -26,13 +26,8 @@ function formatNumber(value) {
    <div class="card-header">
      <div class="card-title">
        明細列表
-        <span v-if="selectedParetoValues.length > 0" class="detail-reason-badge">
-          {{ selectedParetoDimensionLabel || 'Pareto 篩選' }}:
-          {{
-            selectedParetoValues.length === 1
-              ? selectedParetoValues[0]
-              : `${selectedParetoValues.length} 項`
-          }}
+        <span v-if="selectedParetoCount > 0" class="detail-reason-badge">
+          Pareto 篩選: {{ selectedParetoSummary || `${selectedParetoCount} 項` }}
          <button type="button" class="badge-clear" @click="$emit('clear-pareto-selection')">×</button>
        </span>
      </div>
--- a/frontend/src/reject-history/components/FilterPanel.vue
+++ b/frontend/src/reject-history/components/FilterPanel.vue
@@ -12,6 +12,7 @@ const props = defineProps({
  resolutionInfo: { type: Object, default: null },
  loading: { type: Object, required: true },
  activeFilterChips: { type: Array, default: () => [] },
+  paretoDisplayScope: { type: String, default: 'all' },
 });

 const emit = defineEmits([
@@ -20,6 +21,7 @@ const emit = defineEmits([
  'export-csv',
  'remove-chip',
  'pareto-scope-toggle',
+  'pareto-display-scope-change',
  'update:queryMode',
  'update:containerInputType',
  'update:containerInput',
@@ -191,6 +193,15 @@ function emitSupplementary(patch) {
          />
          Pareto 僅顯示累計前 80%
        </label>
+        <label class="filter-label">顯示範圍</label>
+        <select
+          class="dimension-select pareto-scope-select"
+          :value="paretoDisplayScope"
+          @change="$emit('pareto-display-scope-change', $event.target.value)"
+        >
+          <option value="all">全部顯示</option>
+          <option value="top20">只顯示 TOP 20</option>
+        </select>
      </div>
      <div class="supplementary-row">
        <div class="filter-group">
--- a/frontend/src/reject-history/components/ParetoGrid.vue
+++ b/frontend/src/reject-history/components/ParetoGrid.vue
@@ -0,0 +1,45 @@
+<script setup>
+import ParetoSection from './ParetoSection.vue';
+
+const DIMENSIONS = [
+  { key: 'reason', label: '不良原因' },
+  { key: 'package', label: 'PACKAGE' },
+  { key: 'type', label: 'TYPE' },
+  { key: 'workflow', label: 'WORKFLOW' },
+  { key: 'workcenter', label: '站點' },
+  { key: 'equipment', label: '機台' },
+];
+
+const props = defineProps({
+  paretoData: { type: Object, default: () => ({}) },
+  paretoSelections: { type: Object, default: () => ({}) },
+  loading: { type: Boolean, default: false },
+  metricLabel: { type: String, default: '報廢量' },
+  selectedDates: { type: Array, default: () => [] },
+  displayScope: { type: String, default: 'all' },
+});
+
+const emit = defineEmits(['item-toggle']);
+
+function onItemToggle(dimension, value) {
+  emit('item-toggle', dimension, value);
+}
+</script>
+
+<template>
+  <div class="pareto-grid">
+    <ParetoSection
+      v-for="dim in DIMENSIONS"
+      :key="dim.key"
+      :dimension="dim.key"
+      :dimension-label="dim.label"
+      :items="paretoData[dim.key]?.items || []"
+      :selected-values="paretoSelections[dim.key] || []"
+      :selected-dates="selectedDates"
+      :metric-label="metricLabel"
+      :display-scope="displayScope"
+      :loading="loading"
+      @item-toggle="onItemToggle(dim.key, $event)"
+    />
+  </div>
+</template>
--- a/frontend/src/reject-history/components/ParetoSection.vue
+++ b/frontend/src/reject-history/components/ParetoSection.vue
@@ -9,14 +9,6 @@ import VChart from 'vue-echarts';

 use([CanvasRenderer, BarChart, LineChart, GridComponent, TooltipComponent, LegendComponent]);

-const DIMENSION_OPTIONS = [
-  { value: 'reason', label: '不良原因' },
-  { value: 'package', label: 'PACKAGE' },
-  { value: 'type', label: 'TYPE' },
-  { value: 'workflow', label: 'WORKFLOW' },
-  { value: 'workcenter', label: '站點' },
-  { value: 'equipment', label: '機台' },
-];
 const DISPLAY_SCOPE_TOP20_DIMENSIONS = new Set(['type', 'workflow', 'equipment']);

 const props = defineProps({
@@ -26,23 +18,33 @@ const props = defineProps({
  metricLabel: { type: String, default: '報廢量' },
  loading: { type: Boolean, default: false },
  dimension: { type: String, default: 'reason' },
-  showDimensionSelector: { type: Boolean, default: false },
+  dimensionLabel: { type: String, default: 'Pareto' },
  displayScope: { type: String, default: 'all' },
 });

-const emit = defineEmits(['item-toggle', 'dimension-change', 'display-scope-change']);
+const emit = defineEmits(['item-toggle']);

-const hasData = computed(() => Array.isArray(props.items) && props.items.length > 0);
-const selectedValueSet = computed(() => new Set((props.selectedValues || []).map((item) => String(item || '').trim())));
-const showDisplayScopeSelector = computed(
-  () => DISPLAY_SCOPE_TOP20_DIMENSIONS.has(props.dimension),
-);
+const selectedValueSet = computed(
+  () => new Set((props.selectedValues || []).map((item) => String(item || '').trim()),
+));

-const dimensionLabel = computed(() => {
-  const opt = DIMENSION_OPTIONS.find((o) => o.value === props.dimension);
-  return opt ? opt.label : '報廢原因';
+const displayItems = computed(() => {
+  const items = Array.isArray(props.items) ? props.items : [];
+  if (
+    props.displayScope === 'top20'
+    && DISPLAY_SCOPE_TOP20_DIMENSIONS.has(props.dimension)
+  ) {
+    return items.slice(0, 20);
+  }
+  return items;
 });

+const hasData = computed(() => displayItems.value.length > 0);
+
+const showTop20Badge = computed(
+  () => props.displayScope === 'top20' && DISPLAY_SCOPE_TOP20_DIMENSIONS.has(props.dimension),
+);
+
 function isSelected(value) {
  return selectedValueSet.value.has(String(value || '').trim());
 }
@@ -56,7 +58,7 @@ function formatPct(value) {
 }

 const chartOption = computed(() => {
-  const items = props.items || [];
+  const items = displayItems.value;
  return {
    tooltip: {
      trigger: 'axis',
@@ -80,17 +82,18 @@ const chartOption = computed(() => {
      left: 52,
      right: 52,
      top: 20,
-      bottom: 96,
+      bottom: items.length > 10 ? 110 : 96,
    },
    xAxis: {
      type: 'category',
      data: items.map((item) => item.reason || '(未填寫)'),
      axisLabel: {
        interval: 0,
-        rotate: items.length > 6 ? 35 : 0,
-        fontSize: 11,
+        rotate: items.length > 10 ? 55 : items.length > 5 ? 35 : 0,
+        fontSize: items.length > 15 ? 9 : items.length > 8 ? 10 : 11,
        overflow: 'truncate',
-        width: 100,
+        width: items.length > 10 ? 60 : 80,
+        hideOverlap: true,
      },
    },
    yAxis: [
@@ -137,7 +140,7 @@ function handleChartClick(params) {
  if (params?.seriesType !== 'bar') {
    return;
  }
-  const itemValue = props.items?.[params.dataIndex]?.reason;
+  const itemValue = displayItems.value?.[params.dataIndex]?.reason;
  if (itemValue) {
    emit('item-toggle', itemValue);
  }
@@ -149,27 +152,9 @@ function handleChartClick(params) {
    <div class="card-header pareto-header">
      <div class="card-title">
        {{ metricLabel }} vs {{ dimensionLabel }}（Pareto）
+        <span v-if="showTop20Badge" class="pareto-date-badge">TOP 20</span>
        <span v-for="d in selectedDates" :key="d" class="pareto-date-badge">{{ d }}</span>
      </div>
-      <div class="pareto-controls">
-        <select
-          v-if="showDimensionSelector"
-          class="dimension-select"
-          :value="dimension"
-          @change="emit('dimension-change', $event.target.value)"
-        >
-          <option v-for="opt in DIMENSION_OPTIONS" :key="opt.value" :value="opt.value">{{ opt.label }}</option>
-        </select>
-        <select
-          v-if="showDisplayScopeSelector"
-          class="dimension-select pareto-scope-select"
-          :value="displayScope"
-          @change="emit('display-scope-change', $event.target.value)"
-        >
-          <option value="all">全部顯示</option>
-          <option value="top20">只顯示 TOP 20</option>
-        </select>
-      </div>
    </div>
    <div class="card-body pareto-layout">
      <div class="pareto-chart-wrap">
@@ -188,7 +173,7 @@ function handleChartClick(params) {
          </thead>
          <tbody>
            <tr
-              v-for="item in items"
+              v-for="item in displayItems"
              :key="item.reason"
              :class="{ active: isSelected(item.reason) }"
            >
@@ -201,7 +186,7 @@ function handleChartClick(params) {
              <td>{{ formatPct(item.pct) }}</td>
              <td>{{ formatPct(item.cumPct) }}</td>
            </tr>
-            <tr v-if="!items || items.length === 0">
+            <tr v-if="displayItems.length === 0">
              <td colspan="4" class="placeholder">No data</td>
            </tr>
          </tbody>
--- a/frontend/src/reject-history/style.css
+++ b/frontend/src/reject-history/style.css
@@ -54,6 +54,10 @@
 }

 .supplementary-toolbar {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  flex-wrap: wrap;
  margin-bottom: 12px;
 }

@@ -304,11 +308,18 @@
 .chart-wrap,
 .pareto-chart-wrap {
  width: 100%;
-  height: 340px;
+  height: 260px;
  position: relative;
  overflow: hidden;
 }

+.pareto-grid {
+  display: grid;
+  grid-template-columns: repeat(3, minmax(0, 1fr));
+  gap: 14px;
+  margin-bottom: 14px;
+}
+
 .pareto-header {
  display: flex;
  justify-content: space-between;
@@ -350,8 +361,8 @@

 .pareto-layout {
  display: grid;
-  grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
-  gap: 12px;
+  grid-template-columns: minmax(0, 1fr);
+  gap: 10px;
 }

 .pareto-table-wrap {
@@ -618,7 +629,7 @@
  }
 }

-@media (max-width: 1180px) {
+@media (max-width: 1200px) {
  .filter-panel {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
@@ -631,12 +642,12 @@
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

-  .pareto-layout {
-    grid-template-columns: 1fr;
+  .pareto-grid {
+    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
 }

-@media (max-width: 760px) {
+@media (max-width: 768px) {
  .reject-summary-row {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
@@ -662,4 +673,8 @@
    flex-direction: column;
    align-items: flex-start;
  }
+
+  .pareto-grid {
+    grid-template-columns: 1fr;
+  }
 }
--- a/frontend/tests/report-filter-strategy.test.js
+++ b/frontend/tests/report-filter-strategy.test.js
@@ -3,6 +3,7 @@ import assert from 'node:assert/strict';

 import {
  buildRejectOptionsRequestParams,
+  buildViewParams,
  pruneRejectFilterSelections,
 } from '../src/core/reject-history-filters.js';
 import {
@@ -62,6 +63,45 @@ test('reject-history prune removes invalid selected values', () => {
  assert.equal(pruned.removedCount, 3);
 });

+test('reject-history view params include multi-dimension pareto selections', () => {
+  const params = buildViewParams('qid-001', {
+    supplementaryFilters: {
+      packages: ['PKG-A'],
+      workcenterGroups: ['WB'],
+      reason: '001_A',
+    },
+    trendDates: ['2026-02-01'],
+    paretoSelections: {
+      reason: ['001_A'],
+      type: ['TYPE-A', 'TYPE-B'],
+      workflow: ['WF-01'],
+    },
+    page: 2,
+    perPage: 80,
+    policyFilters: {
+      includeExcludedScrap: true,
+      excludeMaterialScrap: false,
+      excludePbDiode: false,
+    },
+  });
+
+  assert.deepEqual(params, {
+    query_id: 'qid-001',
+    packages: ['PKG-A'],
+    workcenter_groups: ['WB'],
+    reason: '001_A',
+    trend_dates: ['2026-02-01'],
+    sel_reason: ['001_A'],
+    sel_type: ['TYPE-A', 'TYPE-B'],
+    sel_workflow: ['WF-01'],
+    page: 2,
+    per_page: 80,
+    include_excluded_scrap: 'true',
+    exclude_material_scrap: 'false',
+    exclude_pb_diode: 'false',
+  });
+});
+
 test('resource-history derives families from upstream group and flags', () => {
  const resources = [
    { id: 'R1', name: 'MC-01', family: 'FAM-A', workcenterGroup: 'WB', isProduction: true, isKey: true, isMonitor: false },
--- a/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/.openspec.yaml
+++ b/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/.openspec.yaml
@@ -0,0 +1,2 @@
+schema: spec-driven
+created: 2026-03-02
--- a/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/design.md
+++ b/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/design.md
@@ -0,0 +1,59 @@
+## Context
+
+The reject history page displays a single Pareto chart with a dropdown to switch between 6 dimensions (reason, package, type, workflow, workcenter, equipment). Users lose cross-dimensional context when switching. The cached dataset in `reject_dataset_cache.py` already supports all 6 dimensions via `compute_dimension_pareto()` and the `_DIM_TO_DF_COLUMN` mapping. The goal is to show all 6 simultaneously in a 3×2 grid with cross-filter linkage.
+
+Current architecture:
+- **Backend**: `compute_dimension_pareto()` computes one dimension at a time from a cached Pandas DataFrame (in-memory, populated by the primary Oracle query and keyed by `query_id`). All Pareto computation is performed on this cached DataFrame — no additional Oracle queries are made.
+- **Frontend**: `App.vue` holds `paretoDimension` (single ref), `selectedParetoValues` (single array), and `paretoDisplayScope`. Client-side reason Pareto is computed via `allParetoItems` computed property from `analyticsRawItems`. Other dimensions call `fetchDimensionPareto()` which hits `GET /api/reject-history/reason-pareto?dimension=X`.
+
+## Goals / Non-Goals
+
+**Goals:**
+- Display all 6 Pareto dimensions simultaneously in a 3-column responsive grid
+- Cross-filter linkage: clicking items in dimension X filters all OTHER dimensions (exclude-self)
+- Detail table reflects ALL dimension selections (AND logic)
+- Single batch API call for all 6 dimensions (avoid 6 round-trips)
+- Unify all Pareto computation on backend (remove client-side reason Pareto)
+
+**Non-Goals:**
+- No changes to the primary query SQL or data model
+- No changes to the cache infrastructure or TTL
+- No new Oracle fallback paths (batch-pareto is cache-only)
+- No drag-and-drop or reorderable grid layout
+
+## Decisions
+
+### 1. Single batch API vs 6 separate calls
+**Decision**: Single `GET /api/reject-history/batch-pareto` endpoint returning all 6 dimensions.
+**Rationale**: Cross-filter requires all dimensions to see each other's selections. A single call eliminates 6 round-trips and guarantees consistency across all 6 results. The cached DataFrame is shared in-memory so iterating 6 dimensions is negligible overhead.
+
+### 2. Cross-filter logic: exclude-self pattern
+**Decision**: When computing dimension X's Pareto, apply selections from all OTHER dimensions but NOT X's own.
+**Rationale**: If X's own selections were applied, the Pareto would only show selected items — defeating the purpose of showing the full distribution. Exclude-self lets users see "given these TYPE and WORKFLOW selections, what is the REASON distribution?"
+
+### 3. Remove client-side reason Pareto
+**Decision**: Remove the `allParetoItems` computed property that builds reason Pareto client-side from `analyticsRawItems`. All 6 dimensions (including reason) computed by backend `compute_batch_pareto()`.
+**Rationale**: Unifies computation path. The backend already has the logic; duplicating it client-side for one dimension creates divergence risk and doesn't support cross-filtering.
+
+### 4. Retain TOP20/ALL display scope toggle
+**Decision**: Keep the TOP20/全部顯示 toggle for applicable dimensions (TYPE, WORKFLOW, 機台). Apply uniformly across all 6 charts via a global control (not per-chart selectors).
+**Rationale**: Even after 80% cumulative filtering, dimensions like TYPE, WORKFLOW, and 機台 can still produce many items. The TOP20 truncation remains valuable for readability in the compact grid layout. Moving to a single global toggle (instead of per-chart selectors) reduces UI clutter while preserving the functionality.
+
+### 5. ParetoGrid wrapper vs inline loop
+**Decision**: New `ParetoGrid.vue` component wrapping 6 `ParetoSection.vue` instances.
+**Rationale**: Separates grid layout concerns from individual chart rendering. `ParetoSection.vue` is simplified to a pure display component. `ParetoGrid.vue` handles the dimension iteration and event delegation.
+
+### 6. Multi-dimension selection URL encoding
+**Decision**: Use `sel_reason`, `sel_package`, `sel_type`, `sel_workflow`, `sel_workcenter`, `sel_equipment` as separate array params (replacing single `pareto_dimension` + `pareto_values`).
+**Rationale**: Each dimension has independent selections. Encoding them as separate params is explicit, debuggable, and backward-compatible (old URLs with `pareto_dimension` simply won't have `sel_*` params).
+
+### 7. Multi-dimension detail/export filter
+**Decision**: Extend `_apply_pareto_selection_filter()` to accept a `pareto_selections: dict` and apply all dimensions cumulatively (AND logic). Keep backward compat with single `pareto_dimension`/`pareto_values` for the existing single-dimension endpoints until they are removed.
+**Rationale**: Detail table and CSV export need to filter by all 6 dimensions simultaneously. AND logic is the natural interpretation: "show rows matching these reasons AND these types AND these workflows."
+
+## Risks / Trade-offs
+
+- **6 charts on screen may feel crowded on smaller screens** → Responsive breakpoints: 3-col desktop, 2-col tablet, 1-col mobile. Chart height reduced from 340px to ~240px.
+- **Batch pareto payload is larger (6× single)** → Still small (6 arrays of ≤20 items each). Negligible compared to the primary query.
+- **Per-chart scope toggles removed in favor of global toggle** → Individual TOP20/ALL selectors inside each chart would clutter the compact grid. A single global TOP20/ALL control in supplementary filters provides the same functionality with cleaner UX.
+- **Cross-filter causes re-fetch on every click** → Mitigated by cache-only computation (no Oracle queries). Typical response time < 50ms.
--- a/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/proposal.md
+++ b/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/proposal.md
@@ -0,0 +1,43 @@
+## Why
+
+目前報廢歷史的柏拉圖一次只顯示一個維度，需透過下拉選單切換，無法同時看到跨維度的分佈與交叉關係。改為同時顯示 6 個柏拉圖（3×2 grid），並支援跨圖即時聯動篩選——點擊任一柏拉圖的項目後，其餘 5 個柏拉圖即時重新計算（排除自身維度的篩選），下方明細表則套用所有維度的篩選結果。
+
+## What Changes
+
+### 前端
+- 移除維度切換下拉選單（`ParetoSection.vue` 的 dimension selector）
+- 新增 `ParetoGrid.vue` 元件，以 3 欄 grid 同時渲染 6 個獨立柏拉圖（不良原因、PACKAGE、TYPE、WORKFLOW、站點、機台）
+- 每個柏拉圖支援多選（現有行為），點擊後即時聯動：
+  - 其他 5 個柏拉圖重新計算（套用來自其他維度的選取，但不套用自身維度的選取）
+  - 明細表套用所有 6 個維度的選取結果
+- 選取狀態以 chip 顯示在明細表上方，按維度分組
+
+### 後端
+- 新增批次柏拉圖 API endpoint（`GET /api/reject-history/batch-pareto`），對快取中的 Pandas DataFrame 進行重算，一次回傳 6 個維度的柏拉圖資料（不重查 Oracle 資料庫）
+- 每個維度的計算套用「排除自身」的交叉篩選邏輯：計算 Reason Pareto 時套用其他 5 維度的選取，但不套用 Reason 自身的選取
+- 移除前端 client-side 的 reason Pareto 計算（統一由後端從快取計算）
+
+### 移除
+- 移除維度切換選單和 `onDimensionChange` 邏輯
+- 移除現有的單維度 `fetchDimensionPareto` 流程
+
+### 保留
+- 保留 TOP20/全部顯示切換功能（TYPE、WORKFLOW、機台維度在 80% 過濾後仍可能有大量項目，TOP20 截斷對使用者仍有價值）
+
+## Capabilities
+
+### New Capabilities
+
+(none)
+
+### Modified Capabilities
+
+- `reject-history-api`: 新增批次柏拉圖 endpoint，支援跨維度交叉篩選
+- `reject-history-page`: 柏拉圖從單維度切換改為 6 圖同時顯示 + 即時聯動
+
+## Impact
+
+- 前端：`App.vue`（狀態管理重構）、`ParetoSection.vue`（改為純展示元件）、新增 `ParetoGrid.vue`
+- 後端：`reject_dataset_cache.py`（新增批次計算，資料來源為快取的 Pandas DataFrame）、`reject_history_routes.py`（新增 endpoint）
+- API：新增 `GET /api/reject-history/batch-pareto` endpoint（cache-only，不查 Oracle）
+- 無資料庫/SQL 變更
--- a/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/specs/reject-history-api/spec.md
+++ b/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/specs/reject-history-api/spec.md
@@ -0,0 +1,78 @@
+## ADDED Requirements
+
+### Requirement: Reject History API SHALL provide batch Pareto endpoint with cross-filter
+The API SHALL provide a batch Pareto endpoint that returns all 6 dimension Pareto results in a single response, supporting cross-dimension filtering with exclude-self logic.
+
+#### Scenario: Batch Pareto response structure
+- **WHEN** `GET /api/reject-history/batch-pareto` is called with valid `query_id`
+- **THEN** response SHALL be `{ success: true, data: { dimensions: { reason: {...}, package: {...}, type: {...}, workflow: {...}, workcenter: {...}, equipment: {...} } } }`
+- **THEN** each dimension object SHALL include `items` array with same schema as reason-pareto items (`reason`, `metric_value`, `pct`, `cumPct`, `MOVEIN_QTY`, `REJECT_TOTAL_QTY`, `DEFECT_QTY`, `count`)
+
+#### Scenario: Cross-filter exclude-self logic
+- **WHEN** `sel_reason=A&sel_type=X` is provided
+- **THEN** reason Pareto SHALL be computed with type=X filter applied (but NOT reason=A filter)
+- **THEN** type Pareto SHALL be computed with reason=A filter applied (but NOT type=X filter)
+- **THEN** package/workflow/workcenter/equipment Paretos SHALL be computed with both reason=A AND type=X filters applied
+
+#### Scenario: Empty selections return unfiltered Paretos
+- **WHEN** batch-pareto is called with no `sel_*` parameters
+- **THEN** all 6 dimensions SHALL return their full Pareto distribution (same as calling reason-pareto individually with no cross-filter)
+
+#### Scenario: Cache-only computation
+- **WHEN** `query_id` does not exist in cache
+- **THEN** the endpoint SHALL return HTTP 400 with error message indicating cache miss
+- **THEN** the endpoint SHALL NOT fall back to Oracle query
+
+#### Scenario: Supplementary and policy filters apply
+- **WHEN** batch-pareto is called with supplementary filters (packages, workcenter_groups, reason) and policy toggles
+- **THEN** all 6 dimension Paretos SHALL be computed after applying policy and supplementary filters first (before cross-filter)
+
+#### Scenario: Data source is cached DataFrame only
+- **WHEN** batch-pareto computes dimension Paretos
+- **THEN** computation SHALL operate on the in-memory cached Pandas DataFrame (populated by the primary query)
+- **THEN** the endpoint SHALL NOT issue any additional Oracle database queries
+- **THEN** response time SHALL be sub-100ms since all computation is in-memory
+
+#### Scenario: Display scope (TOP20) support
+- **WHEN** `pareto_display_scope=top20` is provided
+- **THEN** applicable dimensions (type, workflow, equipment) SHALL truncate results to top 20 items after sorting
+- **WHEN** `pareto_display_scope` is omitted or `all`
+- **THEN** all items SHALL be returned (subject to pareto_scope 80% filter if active)
+
+### Requirement: Reject History API SHALL support multi-dimension Pareto selection in view and export
+The detail view and export endpoints SHALL accept multiple dimension selections simultaneously and apply them with AND logic.
+
+#### Scenario: Multi-dimension filter on view endpoint
+- **WHEN** `GET /api/reject-history/view` is called with `sel_reason=A&sel_type=X`
+- **THEN** returned rows SHALL match reason=A AND type=X (both filters applied simultaneously)
+
+#### Scenario: Multi-dimension filter on export endpoint
+- **WHEN** `GET /api/reject-history/export-cached` is called with `sel_reason=A&sel_type=X`
+- **THEN** exported CSV SHALL contain only rows matching reason=A AND type=X
+
+#### Scenario: Backward compatibility with single-dimension params
+- **WHEN** `pareto_dimension` and `pareto_values` are provided (legacy format)
+- **THEN** the API SHALL still accept and apply them as before
+- **WHEN** both `sel_*` params and legacy params are provided
+- **THEN** `sel_*` params SHALL take precedence
+
+## MODIFIED Requirements
+
+### Requirement: Reject History API SHALL provide reason Pareto endpoint
+The API SHALL return sorted reason distribution data with cumulative percentages. The endpoint supports dimension selection via `dimension` parameter for single-dimension queries.
+
+#### Scenario: Pareto response payload
+- **WHEN** `GET /api/reject-history/reason-pareto` is called
+- **THEN** each item SHALL include `reason`, `category`, selected metric value, `pct`, and `cumPct`
+- **THEN** items SHALL be sorted descending by selected metric
+
+#### Scenario: Metric mode validation
+- **WHEN** `metric_mode` is provided
+- **THEN** accepted values SHALL be `reject_total` or `defect`
+- **THEN** invalid `metric_mode` SHALL return HTTP 400
+
+#### Scenario: Dimension selection
+- **WHEN** `dimension` parameter is provided with a valid value (reason, package, type, workflow, workcenter, equipment)
+- **THEN** the endpoint SHALL return Pareto data for that dimension
+- **WHEN** `dimension` is not provided
+- **THEN** the endpoint SHALL default to `reason`
--- a/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/specs/reject-history-page/spec.md
+++ b/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/specs/reject-history-page/spec.md
@@ -0,0 +1,92 @@
+## MODIFIED Requirements
+
+### Requirement: Reject History page SHALL provide reason Pareto analysis
+The page SHALL display 6 Pareto charts simultaneously (不良原因, PACKAGE, TYPE, WORKFLOW, 站點, 機台) in a 3-column grid layout with cross-filter linkage, replacing the single-dimension dropdown switcher.
+
+#### Scenario: Multi-Pareto grid layout
+- **WHEN** Pareto data is loaded
+- **THEN** 6 Pareto charts SHALL be rendered simultaneously in a 3-column grid (3×2)
+- **THEN** each chart SHALL display one dimension: 不良原因, PACKAGE, TYPE, WORKFLOW, 站點, 機台
+- **THEN** there SHALL be no dimension dropdown selector
+
+#### Scenario: Pareto rendering and ordering
+- **WHEN** Pareto data is loaded
+- **THEN** items in each Pareto SHALL be sorted by selected metric descending
+- **THEN** each Pareto SHALL show a cumulative percentage line
+
+#### Scenario: Pareto 80% filter is managed in supplementary filters
+- **WHEN** the page first loads Pareto
+- **THEN** supplementary filters SHALL include "Pareto 僅顯示累計前 80%" control
+- **THEN** the control SHALL default to enabled
+- **THEN** the 80% filter SHALL apply uniformly to all 6 Pareto charts
+
+#### Scenario: Cross-filter linkage between Pareto charts
+- **WHEN** user clicks an item in one Pareto chart (e.g., selects reason "A")
+- **THEN** the other 5 Pareto charts SHALL recalculate with the selection applied as a filter
+- **THEN** the clicked Pareto chart itself SHALL NOT be filtered by its own selections
+- **THEN** the detail table below SHALL apply ALL selections from ALL dimensions
+
+#### Scenario: Pareto click filtering supports multi-select
+- **WHEN** user clicks Pareto bars or table rows in any dimension
+- **THEN** clicked items SHALL become active selected chips
+- **THEN** multiple selected items SHALL be supported within each dimension
+- **THEN** multiple dimensions SHALL support simultaneous selections
+
+#### Scenario: Re-click clears selected item only
+- **WHEN** user clicks an already selected Pareto item
+- **THEN** only that item SHALL be removed from selection
+- **THEN** remaining selected items across all dimensions SHALL stay active
+- **THEN** all Pareto charts SHALL recalculate to reflect the updated selections
+
+#### Scenario: Filter chips display all dimension selections
+- **WHEN** items are selected across multiple Pareto dimensions
+- **THEN** selected items SHALL be displayed as chips grouped by dimension label
+- **THEN** each chip SHALL show the dimension label and selected value (e.g., "TYPE: X")
+- **THEN** clicking a chip's remove button SHALL deselect that item and trigger recalculation
+
+#### Scenario: Responsive grid layout
+- **WHEN** viewport is desktop width (>1200px)
+- **THEN** Pareto charts SHALL render in a 3-column grid
+- **WHEN** viewport is medium width (768px–1200px)
+- **THEN** Pareto charts SHALL render in a 2-column grid
+- **WHEN** viewport is below 768px
+- **THEN** Pareto charts SHALL stack in a single column
+
+#### Scenario: TOP20/ALL display scope control
+- **WHEN** Pareto grid is displayed
+- **THEN** supplementary filters SHALL include a global "只顯示 TOP 20" toggle
+- **THEN** when enabled, applicable dimensions (TYPE, WORKFLOW, 機台) SHALL truncate to top 20 items
+- **THEN** the toggle SHALL apply uniformly to all applicable Pareto charts (not per-chart selectors)
+- **THEN** dimensions not in the applicable set (不良原因, PACKAGE, 站點) SHALL be unaffected by this toggle
+
+## MODIFIED Requirements
+
+### Requirement: Reject History page SHALL be structured as modular sub-components
+The page template SHALL delegate sections to focused sub-components, following the hold-history architecture pattern.
+
+#### Scenario: Component decomposition
+- **WHEN** the page source is examined
+- **THEN** the filter panel SHALL be a separate `FilterPanel.vue` component
+- **THEN** the KPI summary cards SHALL be a separate `SummaryCards.vue` component
+- **THEN** the trend chart SHALL be a separate `TrendChart.vue` component
+- **THEN** the pareto grid SHALL be a separate `ParetoGrid.vue` component containing 6 `ParetoSection.vue` instances
+- **THEN** each individual pareto chart+table SHALL be a `ParetoSection.vue` component
+- **THEN** the detail table with pagination SHALL be a separate `DetailTable.vue` component
+
+#### Scenario: App.vue acts as orchestrator
+- **WHEN** the page runs
+- **THEN** `App.vue` SHALL hold all reactive state and API logic
+- **THEN** sub-components SHALL receive data via props and communicate via events
+
+### Requirement: Reject History page SHALL support CSV export from current filter context
+The page SHALL allow users to export records using the exact active filters.
+
+#### Scenario: Export with all active filters
+- **WHEN** user clicks "匯出 CSV"
+- **THEN** export request SHALL include current primary filters, supplementary filters, trend-date filters, metric filters, and all Pareto-selected items from all 6 dimensions
+- **THEN** downloaded file SHALL contain exactly the same rows currently represented by the detail list filter context
+
+#### Scenario: Export remains UTF-8 Excel compatible
+- **WHEN** CSV export is downloaded
+- **THEN** the file SHALL be encoded in UTF-8 with BOM
+- **THEN** Chinese headers and values SHALL render correctly in common spreadsheet tools
--- a/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/tasks.md
+++ b/openspec/changes/archive/2026-03-02-reject-history-multi-pareto-layout/tasks.md
@@ -0,0 +1,51 @@
+## 1. Backend — Batch Pareto with Cross-Filter
+
+- [x] 1.1 Add `_apply_cross_filter(df, selections, exclude_dim)` helper in `reject_dataset_cache.py` — applies all dimension selections except `exclude_dim` using `_DIM_TO_DF_COLUMN` mapping
+- [x] 1.2 Add `compute_batch_pareto()` function in `reject_dataset_cache.py` — iterates all 6 dimensions from cached DataFrame (no Oracle query), applies policy → supplementary → trend-date → cross-filter, supports `pareto_display_scope=top20` truncation for applicable dimensions, returns `{"dimensions": {...}}`
+- [x] 1.3 Add `_parse_multi_pareto_selections()` helper in `reject_history_routes.py` — parses `sel_reason`, `sel_package`, `sel_type`, `sel_workflow`, `sel_workcenter`, `sel_equipment` from query params
+- [x] 1.4 Add `GET /api/reject-history/batch-pareto` endpoint in `reject_history_routes.py` — cache-only (no Oracle fallback), accepts `pareto_display_scope` param, calls `compute_batch_pareto()`
+
+## 2. Backend — Multi-Dimension Detail/Export Filter
+
+- [x] 2.1 Extend `_apply_pareto_selection_filter()` in `reject_dataset_cache.py` to accept `pareto_selections: dict` (multi-dimension AND logic), keeping backward compat with single `pareto_dimension`/`pareto_values`
+- [x] 2.2 Update `apply_view()` and `export_csv_from_cache()` in `reject_dataset_cache.py` to pass multi-dimension selections
+- [x] 2.3 Update `view` and `export-cached` endpoints in `reject_history_routes.py` to parse and forward `sel_*` params
+
+## 3. Frontend — State Refactor (App.vue)
+
+- [x] 3.1 Replace single-dimension state (`paretoDimension`, `selectedParetoValues`, `dimensionParetoItems`, `dimensionParetoLoading`) with `paretoSelections` reactive object and `paretoData` reactive object; keep `paretoDisplayScope` ref for global TOP20/ALL toggle
+- [x] 3.2 Add `fetchBatchPareto()` function — calls `GET /api/reject-history/batch-pareto` with `sel_*` params, updates all 6 `paretoData` entries
+- [x] 3.3 Rewrite `onParetoItemToggle(dimension, value)` — toggle in `paretoSelections[dimension]`, call `fetchBatchPareto()` + `refreshView()`, reset page
+- [x] 3.4 Remove dead code: `allParetoItems`, `filteredParetoItems`, `activeParetoItems` computed, `fetchDimensionPareto()`, `refreshDimensionParetoIfActive()`, `onDimensionChange()`, `PARETO_DIMENSION_LABELS`; keep `PARETO_TOP20_DIMENSIONS` and `paretoDisplayScope` for global TOP20/ALL toggle
+- [x] 3.5 Update `activeFilterChips` computed — loop all 6 dimensions, generate chip per selected value with dimension label
+- [x] 3.6 Update chip removal handler to call `onParetoItemToggle(dim, value)`
+
+## 4. Frontend — URL State
+
+- [x] 4.1 Update `updateUrlState()` — replace `pareto_dimension`/`pareto_values` with `sel_reason`, `sel_package`, etc. array params; keep `pareto_display_scope` for TOP20/ALL
+- [x] 4.2 Update `restoreFromUrl()` — parse `sel_*` params into `paretoSelections` object
+- [x] 4.3 Update `buildViewParams()` in `reject-history-filters.js` — replace `paretoDimension`/`paretoValues` with `paretoSelections` dict, emit `sel_*` params
+
+## 5. Frontend — Components
+
+- [x] 5.1 Simplify `ParetoSection.vue` — remove dimension selector dropdown and `DIMENSION_OPTIONS`; keep per-chart TOP20 truncation logic (controlled by parent via `displayScope` prop); add dimension label map; emit `item-toggle` with value only (parent handles dimension routing)
+- [x] 5.2 Create `ParetoGrid.vue` — 3-column grid container rendering 6 `ParetoSection` instances, props: `paretoData`, `paretoSelections`, `loading`, `metricLabel`, `selectedDates`; emit `item-toggle(dimension, value)`
+- [x] 5.3 Update `App.vue` template — replace single `<ParetoSection>` with `<ParetoGrid>`
+
+## 6. Frontend — Styling
+
+- [x] 6.1 Add `.pareto-grid` CSS class in `style.css` — 3-column grid with responsive breakpoints (2-col at ≤1200px, 1-col at ≤768px)
+- [x] 6.2 Adjust `.pareto-chart-wrap` height from 340px to ~240px for compact multi-chart display
+- [x] 6.3 Adjust `.pareto-layout` for vertical stack (chart above table) in grid context
+
+## 7. Integration & Wire-Up
+
+- [x] 7.1 Wire `fetchBatchPareto()` into `loadAllData()` flow — call after primary query completes
+- [x] 7.2 Wire supplementary filter changes and trend-date changes to trigger `fetchBatchPareto()`
+- [x] 7.3 Wire export button to include all 6 dimension selections in export request
+
+## 8. Testing
+
+- [x] 8.1 Add unit tests for `compute_batch_pareto()` cross-filter logic in `tests/test_reject_dataset_cache.py`
+- [x] 8.2 Add route tests for `GET /api/reject-history/batch-pareto` endpoint in `tests/test_reject_history_routes.py`
+- [x] 8.3 Add tests for multi-dimension `_apply_pareto_selection_filter()` in `tests/test_reject_dataset_cache.py`
--- a/openspec/specs/reject-history-api/spec.md
+++ b/openspec/specs/reject-history-api/spec.md
@@ -53,7 +53,7 @@ The API SHALL return time-series trend data for quantity and rate metrics.
 - **THEN** invalid granularity SHALL return HTTP 400

 ### Requirement: Reject History API SHALL provide reason Pareto endpoint
-The API SHALL return sorted reason distribution data with cumulative percentages.
+The API SHALL return sorted reason distribution data with cumulative percentages. The endpoint supports dimension selection via `dimension` parameter for single-dimension queries.

 #### Scenario: Pareto response payload
 - **WHEN** `GET /api/reject-history/reason-pareto` is called
@@ -65,6 +65,68 @@ The API SHALL return sorted reason distribution data with cumulative percentages
 - **THEN** accepted values SHALL be `reject_total` or `defect`
 - **THEN** invalid `metric_mode` SHALL return HTTP 400

+#### Scenario: Dimension selection
+- **WHEN** `dimension` parameter is provided with a valid value (reason, package, type, workflow, workcenter, equipment)
+- **THEN** the endpoint SHALL return Pareto data for that dimension
+- **WHEN** `dimension` is not provided
+- **THEN** the endpoint SHALL default to `reason`
+
+### Requirement: Reject History API SHALL provide batch Pareto endpoint with cross-filter
+The API SHALL provide a batch Pareto endpoint that returns all 6 dimension Pareto results in a single response, supporting cross-dimension filtering with exclude-self logic.
+
+#### Scenario: Batch Pareto response structure
+- **WHEN** `GET /api/reject-history/batch-pareto` is called with valid `query_id`
+- **THEN** response SHALL be `{ success: true, data: { dimensions: { reason: {...}, package: {...}, type: {...}, workflow: {...}, workcenter: {...}, equipment: {...} } } }`
+- **THEN** each dimension object SHALL include `items` array with same schema as reason-pareto items (`reason`, `metric_value`, `pct`, `cumPct`, `MOVEIN_QTY`, `REJECT_TOTAL_QTY`, `DEFECT_QTY`, `count`)
+
+#### Scenario: Cross-filter exclude-self logic
+- **WHEN** `sel_reason=A&sel_type=X` is provided
+- **THEN** reason Pareto SHALL be computed with type=X filter applied (but NOT reason=A filter)
+- **THEN** type Pareto SHALL be computed with reason=A filter applied (but NOT type=X filter)
+- **THEN** package/workflow/workcenter/equipment Paretos SHALL be computed with both reason=A AND type=X filters applied
+
+#### Scenario: Empty selections return unfiltered Paretos
+- **WHEN** batch-pareto is called with no `sel_*` parameters
+- **THEN** all 6 dimensions SHALL return their full Pareto distribution (same as calling reason-pareto individually with no cross-filter)
+
+#### Scenario: Cache-only computation
+- **WHEN** `query_id` does not exist in cache
+- **THEN** the endpoint SHALL return HTTP 400 with error message indicating cache miss
+- **THEN** the endpoint SHALL NOT fall back to Oracle query
+
+#### Scenario: Supplementary and policy filters apply
+- **WHEN** batch-pareto is called with supplementary filters (packages, workcenter_groups, reason) and policy toggles
+- **THEN** all 6 dimension Paretos SHALL be computed after applying policy and supplementary filters first (before cross-filter)
+
+#### Scenario: Data source is cached DataFrame only
+- **WHEN** batch-pareto computes dimension Paretos
+- **THEN** computation SHALL operate on the in-memory cached Pandas DataFrame (populated by the primary query)
+- **THEN** the endpoint SHALL NOT issue any additional Oracle database queries
+- **THEN** response time SHALL be sub-100ms since all computation is in-memory
+
+#### Scenario: Display scope (TOP20) support
+- **WHEN** `pareto_display_scope=top20` is provided
+- **THEN** applicable dimensions (type, workflow, equipment) SHALL truncate results to top 20 items after sorting
+- **WHEN** `pareto_display_scope` is omitted or `all`
+- **THEN** all items SHALL be returned (subject to pareto_scope 80% filter if active)
+
+### Requirement: Reject History API SHALL support multi-dimension Pareto selection in view and export
+The detail view and export endpoints SHALL accept multiple dimension selections simultaneously and apply them with AND logic.
+
+#### Scenario: Multi-dimension filter on view endpoint
+- **WHEN** `GET /api/reject-history/view` is called with `sel_reason=A&sel_type=X`
+- **THEN** returned rows SHALL match reason=A AND type=X (both filters applied simultaneously)
+
+#### Scenario: Multi-dimension filter on export endpoint
+- **WHEN** `GET /api/reject-history/export-cached` is called with `sel_reason=A&sel_type=X`
+- **THEN** exported CSV SHALL contain only rows matching reason=A AND type=X
+
+#### Scenario: Backward compatibility with single-dimension params
+- **WHEN** `pareto_dimension` and `pareto_values` are provided (legacy format)
+- **THEN** the API SHALL still accept and apply them as before
+- **WHEN** both `sel_*` params and legacy params are provided
+- **THEN** `sel_*` params SHALL take precedence
+
 ### Requirement: Reject History API SHALL provide paginated detail endpoint
 The API SHALL return paginated detailed rows for the selected filter context.

--- a/openspec/specs/reject-history-page/spec.md
+++ b/openspec/specs/reject-history-page/spec.md
@@ -74,33 +74,63 @@ The page SHALL show both quantity trend and rate trend to avoid mixing unit scal
 - **THEN** rate values SHALL be displayed as percentages

 ### Requirement: Reject History page SHALL provide reason Pareto analysis
-The page SHALL provide a Pareto view for loss reasons and support downstream filtering.
+The page SHALL display 6 Pareto charts simultaneously (不良原因, PACKAGE, TYPE, WORKFLOW, 站點, 機台) in a 3-column grid layout with cross-filter linkage, replacing the single-dimension dropdown switcher.
+
+#### Scenario: Multi-Pareto grid layout
+- **WHEN** Pareto data is loaded
+- **THEN** 6 Pareto charts SHALL be rendered simultaneously in a 3-column grid (3×2)
+- **THEN** each chart SHALL display one dimension: 不良原因, PACKAGE, TYPE, WORKFLOW, 站點, 機台
+- **THEN** there SHALL be no dimension dropdown selector

 #### Scenario: Pareto rendering and ordering
 - **WHEN** Pareto data is loaded
- **THEN** items SHALL be sorted by selected metric descending
- **THEN** a cumulative percentage line SHALL be shown
+- **THEN** items in each Pareto SHALL be sorted by selected metric descending
+- **THEN** each Pareto SHALL show a cumulative percentage line

 #### Scenario: Pareto 80% filter is managed in supplementary filters
 - **WHEN** the page first loads Pareto
 - **THEN** supplementary filters SHALL include "Pareto 僅顯示累計前 80%" control
 - **THEN** the control SHALL default to enabled
+- **THEN** the 80% filter SHALL apply uniformly to all 6 Pareto charts

-#### Scenario: TYPE/WORKFLOW/機台 support display scope selector
- **WHEN** Pareto dimension is `TYPE`, `WORKFLOW`, or `機台`
- **THEN** the UI SHALL provide `全部顯示` and `只顯示 TOP 20` options
- **THEN** `全部顯示` SHALL still respect the current 80% cumulative filter setting
+#### Scenario: Cross-filter linkage between Pareto charts
+- **WHEN** user clicks an item in one Pareto chart (e.g., selects reason "A")
+- **THEN** the other 5 Pareto charts SHALL recalculate with the selection applied as a filter
+- **THEN** the clicked Pareto chart itself SHALL NOT be filtered by its own selections
+- **THEN** the detail table below SHALL apply ALL selections from ALL dimensions

 #### Scenario: Pareto click filtering supports multi-select
- **WHEN** user clicks Pareto bars or table rows
+- **WHEN** user clicks Pareto bars or table rows in any dimension
 - **THEN** clicked items SHALL become active selected chips
- **THEN** multiple selected items SHALL be supported at the same time
- **THEN** detail list SHALL reload using current selected Pareto items as additional filter criteria
+- **THEN** multiple selected items SHALL be supported within each dimension
+- **THEN** multiple dimensions SHALL support simultaneous selections

 #### Scenario: Re-click clears selected item only
 - **WHEN** user clicks an already selected Pareto item
 - **THEN** only that item SHALL be removed from selection
- **THEN** remaining selected items SHALL stay active
+- **THEN** remaining selected items across all dimensions SHALL stay active
+- **THEN** all Pareto charts SHALL recalculate to reflect the updated selections
+
+#### Scenario: Filter chips display all dimension selections
+- **WHEN** items are selected across multiple Pareto dimensions
+- **THEN** selected items SHALL be displayed as chips grouped by dimension label
+- **THEN** each chip SHALL show the dimension label and selected value (e.g., "TYPE: X")
+- **THEN** clicking a chip's remove button SHALL deselect that item and trigger recalculation
+
+#### Scenario: Responsive grid layout
+- **WHEN** viewport is desktop width (>1200px)
+- **THEN** Pareto charts SHALL render in a 3-column grid
+- **WHEN** viewport is medium width (768px–1200px)
+- **THEN** Pareto charts SHALL render in a 2-column grid
+- **WHEN** viewport is below 768px
+- **THEN** Pareto charts SHALL stack in a single column
+
+#### Scenario: TOP20/ALL display scope control
+- **WHEN** Pareto grid is displayed
+- **THEN** supplementary filters SHALL include a global "只顯示 TOP 20" toggle
+- **THEN** when enabled, applicable dimensions (TYPE, WORKFLOW, 機台) SHALL truncate to top 20 items
+- **THEN** the toggle SHALL apply uniformly to all applicable Pareto charts (not per-chart selectors)
+- **THEN** dimensions not in the applicable set (不良原因, PACKAGE, 站點) SHALL be unaffected by this toggle

 ### Requirement: Reject History page SHALL show paginated detail rows
 The page SHALL provide a paginated detail table for investigation and traceability.
@@ -119,7 +149,7 @@ The page SHALL allow users to export records using the exact active filters.

 #### Scenario: Export with all active filters
 - **WHEN** user clicks "匯出 CSV"
- **THEN** export request SHALL include current primary filters, supplementary filters, trend-date filters, metric filters, and Pareto-selected items
+- **THEN** export request SHALL include current primary filters, supplementary filters, trend-date filters, metric filters, and all Pareto-selected items from all 6 dimensions
 - **THEN** downloaded file SHALL contain exactly the same rows currently represented by the detail list filter context

 #### Scenario: Export remains UTF-8 Excel compatible
@@ -197,7 +227,8 @@ The page template SHALL delegate sections to focused sub-components, following t
 - **THEN** the filter panel SHALL be a separate `FilterPanel.vue` component
 - **THEN** the KPI summary cards SHALL be a separate `SummaryCards.vue` component
 - **THEN** the trend chart SHALL be a separate `TrendChart.vue` component
- **THEN** the pareto section (chart + table) SHALL be a separate `ParetoSection.vue` component
+- **THEN** the pareto grid SHALL be a separate `ParetoGrid.vue` component containing 6 `ParetoSection.vue` instances
+- **THEN** each individual pareto chart+table SHALL be a `ParetoSection.vue` component
 - **THEN** the detail table with pagination SHALL be a separate `DetailTable.vue` component

 #### Scenario: App.vue acts as orchestrator
--- a/src/mes_dashboard/routes/reject_history_routes.py
+++ b/src/mes_dashboard/routes/reject_history_routes.py
@@ -14,6 +14,7 @@ from mes_dashboard.core.rate_limit import configured_rate_limit
 from mes_dashboard.core.utils import parse_bool_query
 from mes_dashboard.services.reject_dataset_cache import (
    apply_view,
+    compute_batch_pareto,
    compute_dimension_pareto,
    execute_primary_query,
    export_csv_from_cache,
@@ -121,6 +122,14 @@ _VALID_PARETO_DIMENSIONS = {
    "workcenter",
    "equipment",
 }
+_PARETO_SELECTION_PARAMS = {
+    "reason": "sel_reason",
+    "package": "sel_package",
+    "type": "sel_type",
+    "workflow": "sel_workflow",
+    "workcenter": "sel_workcenter",
+    "equipment": "sel_equipment",
+}


 def _parse_common_bools() -> tuple[Optional[tuple[dict, int]], bool, bool, bool]:
@@ -161,6 +170,15 @@ def _parse_pareto_selection() -> tuple[Optional[tuple[dict, int]], Optional[str]
    return None, (pareto_dimension or None), (pareto_values or None)


+def _parse_multi_pareto_selections() -> dict[str, list[str]]:
+    selections: dict[str, list[str]] = {}
+    for dim, param_name in _PARETO_SELECTION_PARAMS.items():
+        values = _parse_multi_param(param_name)
+        if values:
+            selections[dim] = values
+    return selections
+
+
@reject_history_bp.route("/api/reject-history/options", methods=["GET"])
 def api_reject_history_options():
    start_date, end_date, date_error = _parse_date_range(required=False)
@@ -363,6 +381,45 @@ def api_reject_history_reason_pareto():
        return jsonify({"success": False, "error": "查詢柏拉圖資料失敗"}), 500


+@reject_history_bp.route("/api/reject-history/batch-pareto", methods=["GET"])
+def api_reject_history_batch_pareto():
+    """Batch pareto view: compute all dimensions from cache only."""
+    query_id = request.args.get("query_id", "").strip()
+    if not query_id:
+        return jsonify({"success": False, "error": "缺少必要參數: query_id"}), 400
+
+    bool_error, include_excluded_scrap, exclude_material_scrap, exclude_pb_diode = _parse_common_bools()
+    if bool_error:
+        return jsonify(bool_error[0]), bool_error[1]
+
+    metric_mode = request.args.get("metric_mode", "reject_total").strip().lower() or "reject_total"
+    pareto_scope = request.args.get("pareto_scope", "top80").strip().lower() or "top80"
+    pareto_display_scope = request.args.get("pareto_display_scope", "all").strip().lower() or "all"
+
+    try:
+        result = compute_batch_pareto(
+            query_id=query_id,
+            metric_mode=metric_mode,
+            pareto_scope=pareto_scope,
+            pareto_display_scope=pareto_display_scope,
+            packages=_parse_multi_param("packages") or None,
+            workcenter_groups=_parse_multi_param("workcenter_groups") or None,
+            reason=request.args.get("reason", "").strip() or None,
+            trend_dates=_parse_multi_param("trend_dates") or None,
+            pareto_selections=_parse_multi_pareto_selections(),
+            include_excluded_scrap=include_excluded_scrap,
+            exclude_material_scrap=exclude_material_scrap,
+            exclude_pb_diode=exclude_pb_diode,
+        )
+        if result is None:
+            return jsonify({"success": False, "error": "cache_miss"}), 400
+        return jsonify({"success": True, "data": result})
+    except ValueError as exc:
+        return jsonify({"success": False, "error": str(exc)}), 400
+    except Exception:
+        return jsonify({"success": False, "error": "查詢批次柏拉圖失敗"}), 500
+
+
@reject_history_bp.route("/api/reject-history/list", methods=["GET"])
@_REJECT_HISTORY_LIST_RATE_LIMIT
 def api_reject_history_list():
@@ -544,6 +601,10 @@ def api_reject_history_view():
    metric_filter = request.args.get("metric_filter", "all").strip().lower() or "all"
    reason = request.args.get("reason", "").strip() or None
    detail_reason = request.args.get("detail_reason", "").strip() or None
+    pareto_selections = _parse_multi_pareto_selections()
+    pareto_dimension = None
+    pareto_values = None
+    if not pareto_selections:
        pareto_error, pareto_dimension, pareto_values = _parse_pareto_selection()
        if pareto_error:
            return jsonify(pareto_error[0]), pareto_error[1]
@@ -563,6 +624,7 @@ def api_reject_history_view():
            detail_reason=detail_reason,
            pareto_dimension=pareto_dimension,
            pareto_values=pareto_values,
+            pareto_selections=pareto_selections or None,
            page=page,
            per_page=per_page,
            include_excluded_scrap=include_excluded_scrap,
@@ -593,6 +655,10 @@ def api_reject_history_export_cached():
    metric_filter = request.args.get("metric_filter", "all").strip().lower() or "all"
    reason = request.args.get("reason", "").strip() or None
    detail_reason = request.args.get("detail_reason", "").strip() or None
+    pareto_selections = _parse_multi_pareto_selections()
+    pareto_dimension = None
+    pareto_values = None
+    if not pareto_selections:
        pareto_error, pareto_dimension, pareto_values = _parse_pareto_selection()
        if pareto_error:
            return jsonify(pareto_error[0]), pareto_error[1]
@@ -612,6 +678,7 @@ def api_reject_history_export_cached():
            detail_reason=detail_reason,
            pareto_dimension=pareto_dimension,
            pareto_values=pareto_values,
+            pareto_selections=pareto_selections or None,
            include_excluded_scrap=include_excluded_scrap,
            exclude_material_scrap=exclude_material_scrap,
            exclude_pb_diode=exclude_pb_diode,
--- a/src/mes_dashboard/services/reject_dataset_cache.py
+++ b/src/mes_dashboard/services/reject_dataset_cache.py
@@ -398,6 +398,7 @@ def apply_view(
    detail_reason: Optional[str] = None,
    pareto_dimension: Optional[str] = None,
    pareto_values: Optional[List[str]] = None,
+    pareto_selections: Optional[Dict[str, List[str]]] = None,
    page: int = 1,
    per_page: int = 50,
    include_excluded_scrap: bool = False,
@@ -446,6 +447,7 @@ def apply_view(
        detail_df,
        pareto_dimension=pareto_dimension,
        pareto_values=pareto_values,
+        pareto_selections=pareto_selections,
    )

    detail_page = _paginate_detail(detail_df, page=page, per_page=per_page)
@@ -514,11 +516,33 @@ def _apply_pareto_selection_filter(
    *,
    pareto_dimension: Optional[str] = None,
    pareto_values: Optional[List[str]] = None,
+    pareto_selections: Optional[Dict[str, List[str]]] = None,
 ) -> pd.DataFrame:
    """Apply Pareto multi-select filters on detail/export datasets."""
    if df is None or df.empty:
        return df

+    normalized_selections = _normalize_pareto_selections(pareto_selections)
+    if normalized_selections:
+        filtered = df
+        for dim in _PARETO_DIMENSIONS:
+            selected_values = normalized_selections.get(dim)
+            if not selected_values:
+                continue
+            dim_col = _DIM_TO_DF_COLUMN.get(dim)
+            if not dim_col:
+                raise ValueError(f"不支援的 pareto_dimension: {dim}")
+            if dim_col not in filtered.columns:
+                return filtered.iloc[0:0]
+            value_set = set(selected_values)
+            normalized_dimension_values = filtered[dim_col].map(
+                lambda value: _normalize_text(value) or "(未知)"
+            )
+            filtered = filtered[normalized_dimension_values.isin(value_set)]
+            if filtered.empty:
+                return filtered
+        return filtered
+
    normalized_values = _normalize_pareto_values(pareto_values)
    if not normalized_values:
        return df
@@ -769,6 +793,143 @@ _DIM_TO_DF_COLUMN = {
    "workcenter": "WORKCENTER_GROUP",
    "equipment": "PRIMARY_EQUIPMENTNAME",
 }
+_PARETO_DIMENSIONS = tuple(_DIM_TO_DF_COLUMN.keys())
+_PARETO_TOP20_DIMENSIONS = {"type", "workflow", "equipment"}
+
+
+def _normalize_metric_mode(metric_mode: str) -> str:
+    mode = _normalize_text(metric_mode).lower()
+    if mode not in {"reject_total", "defect"}:
+        raise ValueError("Invalid metric_mode, supported: reject_total, defect")
+    return mode
+
+
+def _normalize_pareto_scope(pareto_scope: str) -> str:
+    scope = _normalize_text(pareto_scope).lower() or "top80"
+    if scope not in {"top80", "all"}:
+        raise ValueError("Invalid pareto_scope, supported: top80, all")
+    return scope
+
+
+def _normalize_pareto_display_scope(display_scope: str) -> str:
+    scope = _normalize_text(display_scope).lower() or "all"
+    if scope not in {"all", "top20"}:
+        raise ValueError("Invalid pareto_display_scope, supported: all, top20")
+    return scope
+
+
+def _normalize_pareto_selections(
+    pareto_selections: Optional[Dict[str, List[str]]],
+) -> Dict[str, List[str]]:
+    normalized: Dict[str, List[str]] = {}
+    for dim, values in (pareto_selections or {}).items():
+        dim_key = _normalize_text(dim).lower()
+        if not dim_key:
+            continue
+        if dim_key not in _DIM_TO_DF_COLUMN:
+            raise ValueError(f"不支援的 pareto_dimension: {dim}")
+        normalized_values = _normalize_pareto_values(values)
+        if normalized_values:
+            normalized[dim_key] = normalized_values
+    return normalized
+
+
+def _build_dimension_pareto_items(
+    df: pd.DataFrame,
+    *,
+    dim_col: str,
+    metric_mode: str,
+    pareto_scope: str,
+) -> List[Dict[str, Any]]:
+    if df is None or df.empty:
+        return []
+    if dim_col not in df.columns:
+        return []
+
+    metric_col = "DEFECT_QTY" if metric_mode == "defect" else "REJECT_TOTAL_QTY"
+    if metric_col not in df.columns:
+        return []
+
+    agg_dict = {}
+    for col in ["MOVEIN_QTY", "REJECT_TOTAL_QTY", "DEFECT_QTY"]:
+        if col in df.columns:
+            agg_dict[col] = (col, "sum")
+
+    grouped = df.groupby(dim_col, sort=False).agg(**agg_dict).reset_index()
+    if grouped.empty:
+        return []
+
+    if "CONTAINERID" in df.columns:
+        lot_counts = (
+            df.groupby(dim_col)["CONTAINERID"]
+            .nunique()
+            .reset_index()
+            .rename(columns={"CONTAINERID": "AFFECTED_LOT_COUNT"})
+        )
+        grouped = grouped.merge(lot_counts, on=dim_col, how="left")
+    else:
+        grouped["AFFECTED_LOT_COUNT"] = 0
+
+    grouped["METRIC_VALUE"] = grouped[metric_col].fillna(0)
+    grouped = grouped[grouped["METRIC_VALUE"] > 0].sort_values(
+        "METRIC_VALUE", ascending=False
+    )
+    if grouped.empty:
+        return []
+
+    total_metric = grouped["METRIC_VALUE"].sum()
+    grouped["PCT"] = (grouped["METRIC_VALUE"] / total_metric * 100).round(4)
+    grouped["CUM_PCT"] = grouped["PCT"].cumsum().round(4)
+
+    items: List[Dict[str, Any]] = []
+    for _, row in grouped.iterrows():
+        items.append({
+            "reason": _normalize_text(row.get(dim_col)) or "(未知)",
+            "metric_value": _as_float(row.get("METRIC_VALUE")),
+            "MOVEIN_QTY": _as_int(row.get("MOVEIN_QTY")),
+            "REJECT_TOTAL_QTY": _as_int(row.get("REJECT_TOTAL_QTY")),
+            "DEFECT_QTY": _as_int(row.get("DEFECT_QTY")),
+            "count": _as_int(row.get("AFFECTED_LOT_COUNT")),
+            "pct": round(_as_float(row.get("PCT")), 4),
+            "cumPct": round(_as_float(row.get("CUM_PCT")), 4),
+        })
+
+    if pareto_scope == "top80" and items:
+        top_items = [item for item in items if _as_float(item.get("cumPct")) <= 80.0]
+        if not top_items:
+            top_items = [items[0]]
+        return top_items
+    return items
+
+
+def _apply_cross_filter(
+    df: pd.DataFrame,
+    selections: Dict[str, List[str]],
+    exclude_dim: str,
+) -> pd.DataFrame:
+    if df is None or df.empty or not selections:
+        return df
+
+    filtered = df
+    for dim in _PARETO_DIMENSIONS:
+        if dim == exclude_dim:
+            continue
+        selected_values = selections.get(dim)
+        if not selected_values:
+            continue
+        dim_col = _DIM_TO_DF_COLUMN.get(dim)
+        if not dim_col:
+            raise ValueError(f"不支援的 pareto_dimension: {dim}")
+        if dim_col not in filtered.columns:
+            return filtered.iloc[0:0]
+        value_set = set(selected_values)
+        normalized_dimension_values = filtered[dim_col].map(
+            lambda value: _normalize_text(value) or "(未知)"
+        )
+        filtered = filtered[normalized_dimension_values.isin(value_set)]
+        if filtered.empty:
+            return filtered
+    return filtered


 def compute_dimension_pareto(
@@ -786,6 +947,14 @@ def compute_dimension_pareto(
    exclude_pb_diode: bool = True,
 ) -> Optional[Dict[str, Any]]:
    """Compute dimension pareto from cached DataFrame (no Oracle query)."""
+    metric_mode = _normalize_metric_mode(metric_mode)
+    pareto_scope = _normalize_pareto_scope(pareto_scope)
+    dimension = _normalize_text(dimension).lower() or "reason"
+    if dimension not in _DIM_TO_DF_COLUMN:
+        raise ValueError(
+            f"Invalid dimension, supported: {', '.join(sorted(_DIM_TO_DF_COLUMN.keys()))}"
+        )
+
    df = _get_cached_df(query_id)
    if df is None:
        return None
@@ -800,7 +969,7 @@ def compute_dimension_pareto(
    if df is None or df.empty:
        return {"items": [], "dimension": dimension, "metric_mode": metric_mode}

-    dim_col = _DIM_TO_DF_COLUMN.get(dimension, "LOSSREASONNAME")
+    dim_col = _DIM_TO_DF_COLUMN.get(dimension)
    if dim_col not in df.columns:
        return {"items": [], "dimension": dimension, "metric_mode": metric_mode}

@@ -823,66 +992,12 @@ def compute_dimension_pareto(
        if filtered.empty:
            return {"items": [], "dimension": dimension, "metric_mode": metric_mode}

-    # Determine metric column
-    if metric_mode == "defect":
-        metric_col = "DEFECT_QTY"
-    else:
-        metric_col = "REJECT_TOTAL_QTY"
-
-    if metric_col not in filtered.columns:
-        return {"items": [], "dimension": dimension, "metric_mode": metric_mode}
-
-    # Group by dimension
-    agg_dict = {}
-    for col in ["MOVEIN_QTY", "REJECT_TOTAL_QTY", "DEFECT_QTY"]:
-        if col in filtered.columns:
-            agg_dict[col] = (col, "sum")
-
-    grouped = filtered.groupby(dim_col, sort=False).agg(**agg_dict).reset_index()
-
-    # Count distinct lots
-    if "CONTAINERID" in filtered.columns:
-        lot_counts = (
-            filtered.groupby(dim_col)["CONTAINERID"]
-            .nunique()
-            .reset_index()
-            .rename(columns={"CONTAINERID": "AFFECTED_LOT_COUNT"})
+    items = _build_dimension_pareto_items(
+        filtered,
+        dim_col=dim_col,
+        metric_mode=metric_mode,
+        pareto_scope=pareto_scope,
    )
-        grouped = grouped.merge(lot_counts, on=dim_col, how="left")
-    else:
-        grouped["AFFECTED_LOT_COUNT"] = 0
-
-    # Compute metric and sort
-    grouped["METRIC_VALUE"] = grouped[metric_col].fillna(0)
-    grouped = grouped[grouped["METRIC_VALUE"] > 0].sort_values(
-        "METRIC_VALUE", ascending=False
-    )
-    if grouped.empty:
-        return {"items": [], "dimension": dimension, "metric_mode": metric_mode}
-
-    total_metric = grouped["METRIC_VALUE"].sum()
-    grouped["PCT"] = (grouped["METRIC_VALUE"] / total_metric * 100).round(4)
-    grouped["CUM_PCT"] = grouped["PCT"].cumsum().round(4)
-
-    all_items = []
-    for _, row in grouped.iterrows():
-        all_items.append({
-            "reason": _normalize_text(row.get(dim_col)) or "(未知)",
-            "metric_value": _as_float(row.get("METRIC_VALUE")),
-            "MOVEIN_QTY": _as_int(row.get("MOVEIN_QTY")),
-            "REJECT_TOTAL_QTY": _as_int(row.get("REJECT_TOTAL_QTY")),
-            "DEFECT_QTY": _as_int(row.get("DEFECT_QTY")),
-            "count": _as_int(row.get("AFFECTED_LOT_COUNT")),
-            "pct": round(_as_float(row.get("PCT")), 4),
-            "cumPct": round(_as_float(row.get("CUM_PCT")), 4),
-        })
-
-    items = list(all_items)
-    if pareto_scope == "top80" and items:
-        top_items = [item for item in items if _as_float(item.get("cumPct")) <= 80.0]
-        if not top_items:
-            top_items = [items[0]]
-        items = top_items

    return {
        "items": items,
@@ -891,6 +1006,91 @@ def compute_dimension_pareto(
    }


+def compute_batch_pareto(
+    *,
+    query_id: str,
+    metric_mode: str = "reject_total",
+    pareto_scope: str = "top80",
+    pareto_display_scope: str = "all",
+    packages: Optional[List[str]] = None,
+    workcenter_groups: Optional[List[str]] = None,
+    reason: Optional[str] = None,
+    trend_dates: Optional[List[str]] = None,
+    pareto_selections: Optional[Dict[str, List[str]]] = None,
+    include_excluded_scrap: bool = False,
+    exclude_material_scrap: bool = True,
+    exclude_pb_diode: bool = True,
+) -> Optional[Dict[str, Any]]:
+    """Compute all six Pareto dimensions from cached DataFrame (no Oracle query)."""
+    metric_mode = _normalize_metric_mode(metric_mode)
+    pareto_scope = _normalize_pareto_scope(pareto_scope)
+    pareto_display_scope = _normalize_pareto_display_scope(pareto_display_scope)
+    normalized_selections = _normalize_pareto_selections(pareto_selections)
+
+    df = _get_cached_df(query_id)
+    if df is None:
+        return None
+
+    df = _apply_policy_filters(
+        df,
+        include_excluded_scrap=include_excluded_scrap,
+        exclude_material_scrap=exclude_material_scrap,
+        exclude_pb_diode=exclude_pb_diode,
+    )
+    if df is None or df.empty:
+        return {
+            "dimensions": {
+                dim: {"items": [], "dimension": dim, "metric_mode": metric_mode}
+                for dim in _PARETO_DIMENSIONS
+            }
+        }
+
+    filtered = _apply_supplementary_filters(
+        df,
+        packages=packages,
+        workcenter_groups=workcenter_groups,
+        reason=reason,
+    )
+    if filtered is None or filtered.empty:
+        return {
+            "dimensions": {
+                dim: {"items": [], "dimension": dim, "metric_mode": metric_mode}
+                for dim in _PARETO_DIMENSIONS
+            }
+        }
+
+    if trend_dates and "TXN_DAY" in filtered.columns:
+        date_set = set(trend_dates)
+        filtered = filtered[
+            filtered["TXN_DAY"].apply(lambda d: _to_date_str(d) in date_set)
+        ]
+
+    dimensions: Dict[str, Dict[str, Any]] = {}
+    for dim in _PARETO_DIMENSIONS:
+        dim_col = _DIM_TO_DF_COLUMN.get(dim)
+        dim_df = _apply_cross_filter(filtered, normalized_selections, exclude_dim=dim)
+        items = _build_dimension_pareto_items(
+            dim_df,
+            dim_col=dim_col,
+            metric_mode=metric_mode,
+            pareto_scope=pareto_scope,
+        )
+        if pareto_display_scope == "top20" and dim in _PARETO_TOP20_DIMENSIONS:
+            items = items[:20]
+        dimensions[dim] = {
+            "items": items,
+            "dimension": dim,
+            "metric_mode": metric_mode,
+        }
+
+    return {
+        "dimensions": dimensions,
+        "metric_mode": metric_mode,
+        "pareto_scope": pareto_scope,
+        "pareto_display_scope": pareto_display_scope,
+    }
+
+
 # ============================================================
 # CSV export from cache
 # ============================================================
@@ -907,6 +1107,7 @@ def export_csv_from_cache(
    detail_reason: Optional[str] = None,
    pareto_dimension: Optional[str] = None,
    pareto_values: Optional[List[str]] = None,
+    pareto_selections: Optional[Dict[str, List[str]]] = None,
    include_excluded_scrap: bool = False,
    exclude_material_scrap: bool = True,
    exclude_pb_diode: bool = True,
@@ -944,6 +1145,7 @@ def export_csv_from_cache(
        filtered,
        pareto_dimension=pareto_dimension,
        pareto_values=pareto_values,
+        pareto_selections=pareto_selections,
    )

    rows = []
--- a/tests/test_reject_dataset_cache.py
+++ b/tests/test_reject_dataset_cache.py
@@ -186,3 +186,109 @@ def test_apply_view_rejects_invalid_pareto_dimension(monkeypatch):
            pareto_dimension="invalid-dimension",
            pareto_values=["X"],
        )
+
+
+def test_compute_batch_pareto_applies_cross_filter_exclude_self(monkeypatch):
+    df = pd.DataFrame(
+        [
+            {
+                "CONTAINERID": "C1",
+                "TXN_DAY": pd.Timestamp("2026-02-01"),
+                "LOSSREASONNAME": "R-A",
+                "PRODUCTLINENAME": "PKG-1",
+                "PJ_TYPE": "TYPE-1",
+                "WORKFLOWNAME": "WF-1",
+                "WORKCENTER_GROUP": "WB-1",
+                "PRIMARY_EQUIPMENTNAME": "EQ-1",
+                "SCRAP_OBJECTTYPE": "LOT",
+                "LOSSREASON_CODE": "001_A",
+                "MOVEIN_QTY": 100,
+                "REJECT_TOTAL_QTY": 100,
+                "DEFECT_QTY": 0,
+            },
+            {
+                "CONTAINERID": "C2",
+                "TXN_DAY": pd.Timestamp("2026-02-01"),
+                "LOSSREASONNAME": "R-A",
+                "PRODUCTLINENAME": "PKG-2",
+                "PJ_TYPE": "TYPE-2",
+                "WORKFLOWNAME": "WF-2",
+                "WORKCENTER_GROUP": "WB-2",
+                "PRIMARY_EQUIPMENTNAME": "EQ-2",
+                "SCRAP_OBJECTTYPE": "LOT",
+                "LOSSREASON_CODE": "001_A",
+                "MOVEIN_QTY": 100,
+                "REJECT_TOTAL_QTY": 50,
+                "DEFECT_QTY": 0,
+            },
+            {
+                "CONTAINERID": "C3",
+                "TXN_DAY": pd.Timestamp("2026-02-01"),
+                "LOSSREASONNAME": "R-B",
+                "PRODUCTLINENAME": "PKG-1",
+                "PJ_TYPE": "TYPE-2",
+                "WORKFLOWNAME": "WF-2",
+                "WORKCENTER_GROUP": "WB-1",
+                "PRIMARY_EQUIPMENTNAME": "EQ-1",
+                "SCRAP_OBJECTTYPE": "LOT",
+                "LOSSREASON_CODE": "002_B",
+                "MOVEIN_QTY": 100,
+                "REJECT_TOTAL_QTY": 40,
+                "DEFECT_QTY": 0,
+            },
+            {
+                "CONTAINERID": "C4",
+                "TXN_DAY": pd.Timestamp("2026-02-01"),
+                "LOSSREASONNAME": "R-B",
+                "PRODUCTLINENAME": "PKG-3",
+                "PJ_TYPE": "TYPE-3",
+                "WORKFLOWNAME": "WF-3",
+                "WORKCENTER_GROUP": "WB-3",
+                "PRIMARY_EQUIPMENTNAME": "EQ-3",
+                "SCRAP_OBJECTTYPE": "LOT",
+                "LOSSREASON_CODE": "002_B",
+                "MOVEIN_QTY": 100,
+                "REJECT_TOTAL_QTY": 30,
+                "DEFECT_QTY": 0,
+            },
+        ]
+    )
+    monkeypatch.setattr(cache_svc, "_get_cached_df", lambda _query_id: df)
+    monkeypatch.setattr(
+        "mes_dashboard.services.scrap_reason_exclusion_cache.get_excluded_reasons",
+        lambda: [],
+    )
+
+    result = cache_svc.compute_batch_pareto(
+        query_id="qid-batch-1",
+        metric_mode="reject_total",
+        pareto_scope="all",
+        include_excluded_scrap=True,
+        pareto_selections={
+            "reason": ["R-A"],
+            "type": ["TYPE-2"],
+        },
+    )
+
+    reason_items = result["dimensions"]["reason"]["items"]
+    type_items = result["dimensions"]["type"]["items"]
+    package_items = result["dimensions"]["package"]["items"]
+
+    assert {item["reason"] for item in reason_items} == {"R-A", "R-B"}
+    assert {item["reason"] for item in type_items} == {"TYPE-1", "TYPE-2"}
+    assert [item["reason"] for item in package_items] == ["PKG-2"]
+
+
+def test_apply_pareto_selection_filter_supports_multi_dimension_and_logic():
+    df = _build_detail_filter_df()
+
+    filtered = cache_svc._apply_pareto_selection_filter(
+        df,
+        pareto_selections={
+            "reason": ["001_A"],
+            "type": ["TYPE-B"],
+        },
+    )
+
+    assert len(filtered) == 1
+    assert set(filtered["CONTAINERNAME"].tolist()) == {"LOT-002"}
--- a/tests/test_reject_history_routes.py
+++ b/tests/test_reject_history_routes.py
@@ -256,6 +256,54 @@ class TestRejectHistoryApiRoutes(TestRejectHistoryRoutesBase):
        self.assertIs(kwargs['exclude_pb_diode'], False)
        mock_sql_pareto.assert_not_called()

+    @patch('mes_dashboard.routes.reject_history_routes.compute_batch_pareto')
+    def test_batch_pareto_passes_multi_dimension_selection_params(self, mock_batch_pareto):
+        mock_batch_pareto.return_value = {
+            'dimensions': {
+                'reason': {'items': []},
+                'package': {'items': []},
+                'type': {'items': []},
+                'workflow': {'items': []},
+                'workcenter': {'items': []},
+                'equipment': {'items': []},
+            }
+        }
+
+        response = self.client.get(
+            '/api/reject-history/batch-pareto'
+            '?query_id=qid-001'
+            '&metric_mode=reject_total'
+            '&pareto_scope=all'
+            '&pareto_display_scope=top20'
+            '&sel_reason=001_A'
+            '&sel_type=TYPE-A'
+            '&sel_type=TYPE-B'
+            '&include_excluded_scrap=true'
+            '&exclude_material_scrap=false'
+            '&exclude_pb_diode=false'
+        )
+        payload = json.loads(response.data)
+
+        self.assertEqual(response.status_code, 200)
+        self.assertTrue(payload['success'])
+        _, kwargs = mock_batch_pareto.call_args
+        self.assertEqual(kwargs['query_id'], 'qid-001')
+        self.assertEqual(kwargs['pareto_display_scope'], 'top20')
+        self.assertEqual(kwargs['pareto_scope'], 'all')
+        self.assertEqual(kwargs['pareto_selections'], {'reason': ['001_A'], 'type': ['TYPE-A', 'TYPE-B']})
+        self.assertIs(kwargs['include_excluded_scrap'], True)
+        self.assertIs(kwargs['exclude_material_scrap'], False)
+        self.assertIs(kwargs['exclude_pb_diode'], False)
+
+    @patch('mes_dashboard.routes.reject_history_routes.compute_batch_pareto', return_value=None)
+    def test_batch_pareto_cache_miss_returns_400(self, _mock_batch_pareto):
+        response = self.client.get('/api/reject-history/batch-pareto?query_id=missing-qid')
+        payload = json.loads(response.data)
+
+        self.assertEqual(response.status_code, 400)
+        self.assertFalse(payload['success'])
+        self.assertEqual(payload['error'], 'cache_miss')
+
    @patch('mes_dashboard.routes.reject_history_routes.apply_view')
    def test_view_passes_pareto_multi_select_filters(self, mock_apply_view):
        mock_apply_view.return_value = {
@@ -296,6 +344,58 @@ class TestRejectHistoryApiRoutes(TestRejectHistoryRoutesBase):
        self.assertFalse(payload['success'])
        mock_apply_view.assert_not_called()

+    @patch('mes_dashboard.routes.reject_history_routes.apply_view')
+    def test_view_passes_multi_dimension_selection_filters(self, mock_apply_view):
+        mock_apply_view.return_value = {
+            'analytics_raw': [],
+            'summary': {},
+            'detail': {'items': [], 'pagination': {'page': 1, 'perPage': 50, 'total': 0, 'totalPages': 1}},
+        }
+
+        response = self.client.get(
+            '/api/reject-history/view'
+            '?query_id=qid-001'
+            '&sel_reason=001_A'
+            '&sel_type=TYPE-A'
+            '&sel_workflow=WF-01'
+        )
+        payload = json.loads(response.data)
+
+        self.assertEqual(response.status_code, 200)
+        self.assertTrue(payload['success'])
+        _, kwargs = mock_apply_view.call_args
+        self.assertEqual(kwargs['pareto_selections'], {
+            'reason': ['001_A'],
+            'type': ['TYPE-A'],
+            'workflow': ['WF-01'],
+        })
+        self.assertIsNone(kwargs['pareto_dimension'])
+        self.assertIsNone(kwargs['pareto_values'])
+
+    @patch('mes_dashboard.routes.reject_history_routes.apply_view')
+    def test_view_sel_filters_take_precedence_over_legacy_dimension(self, mock_apply_view):
+        mock_apply_view.return_value = {
+            'analytics_raw': [],
+            'summary': {},
+            'detail': {'items': [], 'pagination': {'page': 1, 'perPage': 50, 'total': 0, 'totalPages': 1}},
+        }
+
+        response = self.client.get(
+            '/api/reject-history/view'
+            '?query_id=qid-001'
+            '&sel_reason=001_A'
+            '&pareto_dimension=invalid'
+            '&pareto_values=bad'
+        )
+        payload = json.loads(response.data)
+
+        self.assertEqual(response.status_code, 200)
+        self.assertTrue(payload['success'])
+        _, kwargs = mock_apply_view.call_args
+        self.assertEqual(kwargs['pareto_selections'], {'reason': ['001_A']})
+        self.assertIsNone(kwargs['pareto_dimension'])
+        self.assertIsNone(kwargs['pareto_values'])
+
    @patch('mes_dashboard.routes.reject_history_routes._list_to_csv')
    @patch('mes_dashboard.routes.reject_history_routes.export_csv_from_cache')
    def test_export_cached_passes_pareto_multi_select_filters(
@@ -333,6 +433,34 @@ class TestRejectHistoryApiRoutes(TestRejectHistoryRoutesBase):
        self.assertFalse(payload['success'])
        mock_export_cached.assert_not_called()

+    @patch('mes_dashboard.routes.reject_history_routes._list_to_csv')
+    @patch('mes_dashboard.routes.reject_history_routes.export_csv_from_cache')
+    def test_export_cached_passes_multi_dimension_selection_filters(
+        self,
+        mock_export_cached,
+        mock_list_to_csv,
+    ):
+        mock_export_cached.return_value = [{'LOT': 'LOT-001'}]
+        mock_list_to_csv.return_value = iter(['A,B\n', '1,2\n'])
+
+        response = self.client.get(
+            '/api/reject-history/export-cached'
+            '?query_id=qid-001'
+            '&sel_reason=001_A'
+            '&sel_type=TYPE-A'
+            '&sel_equipment=EQ-01'
+        )
+
+        self.assertEqual(response.status_code, 200)
+        _, kwargs = mock_export_cached.call_args
+        self.assertEqual(kwargs['pareto_selections'], {
+            'reason': ['001_A'],
+            'type': ['TYPE-A'],
+            'equipment': ['EQ-01'],
+        })
+        self.assertIsNone(kwargs['pareto_dimension'])
+        self.assertIsNone(kwargs['pareto_values'])
+
    @patch('mes_dashboard.routes.reject_history_routes.query_list')
    @patch('mes_dashboard.core.rate_limit.check_and_record', return_value=(True, 6))
    def test_list_rate_limited_returns_429(self, _mock_limit, mock_list):