diff --git a/frontend/package.json.md5 b/frontend/package.json.md5
index 0f8f4fe..a7661c0 100755
--- a/frontend/package.json.md5
+++ b/frontend/package.json.md5
@@ -1 +1 @@
-5b8157374dae5f9340e31b2d0bd2c00e
\ No newline at end of file
+d0f9366af59a6367ad3c7e2d4185ead4
\ No newline at end of file
diff --git a/frontend/src/components/DataGrid.tsx b/frontend/src/components/DataGrid.tsx
index 7a1a604..6bf7aaa 100644
--- a/frontend/src/components/DataGrid.tsx
+++ b/frontend/src/components/DataGrid.tsx
@@ -9,7 +9,7 @@ import ImportPreviewModal from './ImportPreviewModal';
 import { useStore } from '../store';
 import { v4 as uuidv4 } from 'uuid';
 import 'react-resizable/css/styles.css';
-import { buildWhereSQL, escapeLiteral, quoteIdentPart, quoteQualifiedIdent, type FilterCondition } from '../utils/sql';
+import { buildOrderBySQL, buildWhereSQL, escapeLiteral, quoteIdentPart, quoteQualifiedIdent, type FilterCondition } from '../utils/sql';
 import { isMacLikePlatform, normalizeOpacityForPlatform } from '../utils/appearance';
 
 // --- Error Boundary ---
@@ -1819,13 +1819,11 @@ const DataGrid: React.FC<DataGridProps> = ({
       if (!tableName || !pagination) return '';
       const whereSQL = buildWhereSQL(dbType, filterConditions);
       let sql = `SELECT * FROM ${quoteQualifiedIdent(dbType, tableName)} ${whereSQL}`;
-      if (sortInfo && sortInfo.order) {
-          sql += ` ORDER BY ${quoteIdentPart(dbType, sortInfo.columnKey)} ${sortInfo.order === 'ascend' ? 'ASC' : 'DESC'}`;
-      }
+      sql += buildOrderBySQL(dbType, sortInfo, pkColumns);
       const offset = (pagination.current - 1) * pagination.pageSize;
       sql += ` LIMIT ${pagination.pageSize} OFFSET ${offset}`;
       return sql;
-  }, [tableName, pagination, filterConditions, sortInfo]);
+  }, [tableName, pagination, filterConditions, sortInfo, pkColumns]);
 
   // Context Menu Export
   const handleExportSelected = useCallback(async (format: string, record: any) => {
diff --git a/frontend/src/components/DataViewer.tsx b/frontend/src/components/DataViewer.tsx
index 1ca4b8c..cdc132d 100644
--- a/frontend/src/components/DataViewer.tsx
+++ b/frontend/src/components/DataViewer.tsx
@@ -4,7 +4,7 @@ import { TabData, ColumnDefinition } from '../types';
 import { useStore } from '../store';
 import { DBQuery, DBGetColumns } from '../../wailsjs/go/app/App';
 import DataGrid, { GONAVI_ROW_KEY } from './DataGrid';
-import { buildWhereSQL, quoteIdentPart, quoteQualifiedIdent, type FilterCondition } from '../utils/sql';
+import { buildOrderBySQL, buildWhereSQL, quoteQualifiedIdent, type FilterCondition } from '../utils/sql';
 
 const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
   const [data, setData] = useState<any[]>([]);
@@ -69,9 +69,7 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
     const countSql = `SELECT COUNT(*) as total FROM ${quoteQualifiedIdent(dbType, tableName)} ${whereSQL}`;
     
     let sql = `SELECT * FROM ${quoteQualifiedIdent(dbType, tableName)} ${whereSQL}`;
-    if (sortInfo && sortInfo.order) {
-        sql += ` ORDER BY ${quoteIdentPart(dbType, sortInfo.columnKey)} ${sortInfo.order === 'ascend' ? 'ASC' : 'DESC'}`;
-    }
+    sql += buildOrderBySQL(dbType, sortInfo, pkColumns);
     const offset = (page - 1) * size;
     // 大表性能：打开表不阻塞在 COUNT(*)，先通过多取 1 条判断是否还有下一页；总数在后台统计并异步回填。
     sql += ` LIMIT ${size + 1} OFFSET ${offset}`;
@@ -205,13 +203,9 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
         });
     }
     if (fetchSeqRef.current === seq) setLoading(false);
-  }, [connections, tab, sortInfo, filterConditions, pkColumns.length]); 
-  // Depend on pkColumns.length to avoid loop? No, pkColumns is updated inside.
-  // Actually, 'pkColumns' state shouldn't trigger re-fetch.
-  // The 'if (pkColumns.length === 0)' check is inside.
-  // So adding pkColumns to dependency is safer but might trigger double fetch if not careful?
-  // Only if pkColumns changes. It changes once from [] to [...].
-  // So it's fine.
+  }, [connections, tab, sortInfo, filterConditions, pkColumns]); 
+  // 依赖 pkColumns：在无手动排序时可回退到主键稳定排序。
+  // 主键信息只会在首次加载后更新一次，避免循环查询。
 
   // Handlers memoized
   const handleReload = useCallback(() => {
diff --git a/frontend/src/utils/sql.ts b/frontend/src/utils/sql.ts
index 6aca539..0571c99 100644
--- a/frontend/src/utils/sql.ts
+++ b/frontend/src/utils/sql.ts
@@ -63,6 +63,41 @@ export const quoteQualifiedIdent = (dbType: string, ident: string) => {
 
 export const escapeLiteral = (val: string) => (val || '').replace(/'/g, "''");
 
+type SortInfo = {
+  columnKey?: string;
+  order?: string;
+} | null | undefined;
+
+export const buildOrderBySQL = (
+  dbType: string,
+  sortInfo: SortInfo,
+  fallbackColumns: string[] = [],
+) => {
+  const sortColumn = normalizeIdentPart(String(sortInfo?.columnKey || ''));
+  const sortOrder = String(sortInfo?.order || '');
+  const direction = sortOrder === 'ascend' ? 'ASC' : sortOrder === 'descend' ? 'DESC' : '';
+  if (sortColumn && direction) {
+    return ` ORDER BY ${quoteIdentPart(dbType, sortColumn)} ${direction}`;
+  }
+
+  const seen = new Set<string>();
+  const stableColumns = (fallbackColumns || [])
+    .map((col) => normalizeIdentPart(String(col || '')))
+    .filter((col) => {
+      if (!col) return false;
+      const key = col.toLowerCase();
+      if (seen.has(key)) return false;
+      seen.add(key);
+      return true;
+    });
+  if (stableColumns.length > 0) {
+    const parts = stableColumns.map((col) => `${quoteIdentPart(dbType, col)} ASC`);
+    return ` ORDER BY ${parts.join(', ')}`;
+  }
+
+  return '';
+};
+
 export const parseListValues = (val: string) => {
   const raw = (val || '').trim();
   if (!raw) return [];