🐛 fix(db-compat): 修复PG系建表语句兼容并优化DuckDB大表总数统计

- 统一 DBShowCreateTable 与导出链路的 DDL 兜底逻辑，修复 Kingbase/Postgres 占位语句问题
- 增强 custom driver 到 postgres/kingbase/highgo/vastbase 的映射并补充回归测试
- DuckDB 关闭自动后台 COUNT(*)，避免大文件场景翻页与查询卡顿
- 新增近似总数展示、手动精确统计与取消统计交互
- 新增 DBQueryIsolated 独立连接查询能力并同步前端 wailsjs 接口
- refs #136

frontend/src/components/DataGrid.tsx

@@ -509,7 +509,17 @@ interface DataGridProps {
     onReload?: () => void;
     onSort?: (field: string, order: string) => void;
     onPageChange?: (page: number, size: number) => void;
-    pagination?: { current: number, pageSize: number, total: number, totalKnown?: boolean };
+    pagination?: {
+        current: number,
+        pageSize: number,
+        total: number,
+        totalKnown?: boolean,
+        totalApprox?: boolean,
+        totalCountLoading?: boolean,
+        totalCountCancelled?: boolean,
+    };
+    onRequestTotalCount?: () => void;
+    onCancelTotalCount?: () => void;
     sortInfoExternal?: { columnKey: string, order: string } | null;
     // Filtering
     showFilter?: boolean;
@@ -534,7 +544,7 @@ type ColumnMeta = {
 
 const DataGrid: React.FC<DataGridProps> = ({ 
     data, columnNames, loading, tableName, dbName, connectionId, pkColumns = [], readOnly = false,
-    onReload, onSort, onPageChange, pagination, sortInfoExternal, showFilter, onToggleFilter, onApplyFilter
+    onReload, onSort, onPageChange, pagination, onRequestTotalCount, onCancelTotalCount, sortInfoExternal, showFilter, onToggleFilter, onApplyFilter
 }) => {
   const connections = useStore(state => state.connections);
   const addSqlLog = useStore(state => state.addSqlLog);
@@ -2527,6 +2537,26 @@ const DataGrid: React.FC<DataGridProps> = ({
                </>
            )}
 
+           {isDuckDBConnection && onRequestTotalCount && (
+               <>
+                   <div style={{ width: 1, background: '#eee', height: 20, margin: '0 8px' }} />
+                   <Tooltip title={pagination?.totalCountLoading ? '取消本次精确总数统计（不会影响当前浏览）' : '按当前筛选统计精确总数'}>
+                       <Button
+                           icon={pagination?.totalCountLoading ? <CloseOutlined /> : <VerticalAlignBottomOutlined />}
+                           onClick={() => {
+                               if (pagination?.totalCountLoading) {
+                                   if (onCancelTotalCount) onCancelTotalCount();
+                                   return;
+                               }
+                               onRequestTotalCount();
+                           }}
+                       >
+                           {pagination?.totalCountLoading ? '取消统计' : '统计总数'}
+                       </Button>
+                   </Tooltip>
+               </>
+           )}
+
            <div style={{ marginLeft: 'auto' }} />
 	           <div style={{ flexShrink: 0 }}>
 	               <Popover
@@ -3091,12 +3121,20 @@ const DataGrid: React.FC<DataGridProps> = ({
                    pageSize={pagination.pageSize}
                    total={pagination.total}
                    showTotal={(total, range) => {
+                       const hasValidRange = Array.isArray(range) && range[0] > 0 && range[1] >= range[0];
+                       const currentCount = hasValidRange ? Math.max(0, range[1] - range[0] + 1) : 0;
+                       if (pagination.totalKnown === false) {
+                           if (isDuckDBConnection) {
+                               if (pagination.totalCountLoading) return `当前 ${currentCount} 条 / 正在统计精确总数...`;
+                               if (pagination.totalApprox && Number.isFinite(total) && total > 0) return `当前 ${currentCount} 条 / 约 ${total} 条`;
+                               if (pagination.totalCountCancelled) return `当前 ${currentCount} 条 / 已取消统计`;
+                               return `当前 ${currentCount} 条 / 总数未统计`;
+                           }
+                           return `当前 ${currentCount} 条 / 正在统计总数...`;
+                       }
                        if (isDuckDBConnection && (!Number.isFinite(total) || total <= 0)) {
-                           if (pagination.totalKnown === false) return '当前 0 条 / 正在统计总数...';
                            return '当前 0 条 / 共 0 条';
                        }
-                       const currentCount = Math.max(0, range[1] - range[0] + 1);
-                       if (pagination.totalKnown === false) return `当前 ${currentCount} 条 / 正在统计总数...`;
                        return `当前 ${currentCount} 条 / 共 ${total} 条`;
                    }}
                    showSizeChanger

frontend/src/components/DataViewer.tsx

@@ -2,10 +2,20 @@ import React, { useEffect, useState, useCallback, useRef } from 'react';
 import { message } from 'antd';
 import { TabData, ColumnDefinition } from '../types';
 import { useStore } from '../store';
-import { DBQuery, DBGetColumns } from '../../wailsjs/go/app/App';
+import { DBQuery, DBGetColumns, DBQueryIsolated } from '../../wailsjs/go/app/App';
 import DataGrid, { GONAVI_ROW_KEY } from './DataGrid';
 import { buildOrderBySQL, buildWhereSQL, quoteQualifiedIdent, withSortBufferTuningSQL, type FilterCondition } from '../utils/sql';
 
+type ViewerPaginationState = {
+  current: number;
+  pageSize: number;
+  total: number;
+  totalKnown: boolean;
+  totalApprox: boolean;
+  totalCountLoading: boolean;
+  totalCountCancelled: boolean;
+};
+
 const toNonNegativeFiniteNumber = (value: unknown): number | null => {
   if (typeof value === 'number') {
     return Number.isFinite(value) && value >= 0 ? value : null;
@@ -43,6 +53,61 @@ const parseTotalFromCountRow = (row: any): number | null => {
   return null;
 };
 
+const parseDuckDBApproxTotalRow = (row: any): number | null => {
+  if (!row || typeof row !== 'object') return null;
+  const entries = Object.entries(row as Record<string, unknown>);
+  if (entries.length === 0) return null;
+
+  const preferredKeys = ['approx_total', 'estimated_size', 'estimated_rows', 'row_count', 'count', 'total'];
+  for (const preferred of preferredKeys) {
+    for (const [key, raw] of entries) {
+      if (String(key || '').trim().toLowerCase() !== preferred) continue;
+      const parsed = toNonNegativeFiniteNumber(raw);
+      if (parsed !== null) return parsed;
+    }
+  }
+
+  for (const [key, raw] of entries) {
+    const normalized = String(key || '').trim().toLowerCase();
+    if (normalized.includes('estimate') || normalized.includes('row') || normalized.includes('count') || normalized.includes('total')) {
+      const parsed = toNonNegativeFiniteNumber(raw);
+      if (parsed !== null) return parsed;
+    }
+  }
+  return null;
+};
+
+const normalizeDuckDBIdentifier = (raw: string): string => {
+  const text = String(raw || '').trim();
+  if (text.length >= 2) {
+    const first = text[0];
+    const last = text[text.length - 1];
+    if ((first === '"' && last === '"') || (first === '`' && last === '`')) {
+      return text.slice(1, -1).trim();
+    }
+  }
+  return text;
+};
+
+const resolveDuckDBSchemaAndTable = (dbName: string, tableName: string) => {
+  const rawTable = String(tableName || '').trim();
+  if (!rawTable) return { schemaName: 'main', pureTableName: '' };
+
+  const parts = rawTable.split('.');
+  if (parts.length >= 2) {
+    const pureTableName = normalizeDuckDBIdentifier(parts[parts.length - 1]);
+    const schemaName = normalizeDuckDBIdentifier(parts[parts.length - 2]);
+    if (schemaName && pureTableName) {
+      return { schemaName, pureTableName };
+    }
+  }
+
+  const fallbackSchema = normalizeDuckDBIdentifier(String(dbName || '').trim()) || 'main';
+  return { schemaName: fallbackSchema, pureTableName: normalizeDuckDBIdentifier(rawTable) };
+};
+
+const escapeSQLLiteral = (value: string): string => String(value || '').replace(/'/g, "''");
+
 const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
   const [data, setData] = useState<any[]>([]);
   const [columnNames, setColumnNames] = useState<string[]>([]);
@@ -53,14 +118,26 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
   const fetchSeqRef = useRef(0);
   const countSeqRef = useRef(0);
   const countKeyRef = useRef<string>('');
+  const duckdbApproxSeqRef = useRef(0);
+  const duckdbApproxKeyRef = useRef<string>('');
+  const manualCountSeqRef = useRef(0);
+  const manualCountKeyRef = useRef<string>('');
   const pkSeqRef = useRef(0);
   const pkKeyRef = useRef<string>('');
+  const latestConfigRef = useRef<any>(null);
+  const latestDbTypeRef = useRef<string>('');
+  const latestDbNameRef = useRef<string>('');
+  const latestCountSqlRef = useRef<string>('');
+  const latestCountKeyRef = useRef<string>('');
 
-  const [pagination, setPagination] = useState({
+  const [pagination, setPagination] = useState<ViewerPaginationState>({
       current: 1,
       pageSize: 100,
       total: 0,
-      totalKnown: false
+      totalKnown: false,
+      totalApprox: false,
+      totalCountLoading: false,
+      totalCountCancelled: false,
   });
 
   const [sortInfo, setSortInfo] = useState<{ columnKey: string, order: string } | null>(null);
@@ -70,13 +147,106 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
   const currentConnType = (connections.find(c => c.id === tab.connectionId)?.config?.type || '').toLowerCase();
   const forceReadOnly = currentConnType === 'tdengine' || currentConnType === 'clickhouse';
 
+  const runIsolatedQuery = useCallback(async (queryConfig: any, dbName: string, sql: string) => {
+    return DBQueryIsolated(queryConfig as any, dbName, sql);
+  }, []);
+
   useEffect(() => {
     setPkColumns([]);
     pkKeyRef.current = '';
     countKeyRef.current = '';
-    setPagination(prev => ({ ...prev, current: 1, total: 0, totalKnown: false }));
+    duckdbApproxKeyRef.current = '';
+    manualCountKeyRef.current = '';
+    latestConfigRef.current = null;
+    latestDbTypeRef.current = '';
+    latestDbNameRef.current = '';
+    latestCountSqlRef.current = '';
+    latestCountKeyRef.current = '';
+    setPagination(prev => ({
+      ...prev,
+      current: 1,
+      total: 0,
+      totalKnown: false,
+      totalApprox: false,
+      totalCountLoading: false,
+      totalCountCancelled: false,
+    }));
   }, [tab.connectionId, tab.dbName, tab.tableName]);
 
+  const handleDuckDBManualCount = useCallback(async () => {
+    if (latestDbTypeRef.current !== 'duckdb') {
+      return;
+    }
+    const config = latestConfigRef.current;
+    const dbName = latestDbNameRef.current;
+    const countSql = latestCountSqlRef.current;
+    const countKey = latestCountKeyRef.current;
+
+    if (!config || !countSql || !countKey) {
+      message.warning('当前结果集尚未就绪，请先执行一次加载');
+      return;
+    }
+
+    manualCountKeyRef.current = countKey;
+    const countSeq = ++manualCountSeqRef.current;
+    const countStart = Date.now();
+    setPagination(prev => ({ ...prev, totalCountLoading: true, totalCountCancelled: false }));
+    const countConfig: any = { ...(config as any), timeout: 120 };
+
+    try {
+      const resCount = await runIsolatedQuery(countConfig, dbName, countSql);
+      const countDuration = Date.now() - countStart;
+      addSqlLog({
+        id: `log-${Date.now()}-duckdb-manual-count`,
+        timestamp: Date.now(),
+        sql: countSql,
+        status: resCount?.success ? 'success' : 'error',
+        duration: countDuration,
+        message: resCount?.success ? '' : String(resCount?.message || '统计失败'),
+        dbName
+      });
+
+      if (manualCountSeqRef.current !== countSeq) return;
+      if (manualCountKeyRef.current !== countKey) return;
+
+      if (!resCount?.success) {
+        setPagination(prev => ({ ...prev, totalCountLoading: false }));
+        message.error(String(resCount?.message || '统计总数失败'));
+        return;
+      }
+      if (!Array.isArray(resCount.data) || resCount.data.length === 0) {
+        setPagination(prev => ({ ...prev, totalCountLoading: false }));
+        return;
+      }
+
+      const total = parseTotalFromCountRow(resCount.data[0]);
+      if (total === null) {
+        setPagination(prev => ({ ...prev, totalCountLoading: false }));
+        message.error('统计结果解析失败');
+        return;
+      }
+
+      setPagination(prev => ({
+        ...prev,
+        total,
+        totalKnown: true,
+        totalApprox: false,
+        totalCountLoading: false,
+        totalCountCancelled: false,
+      }));
+    } catch (e: any) {
+      if (manualCountSeqRef.current !== countSeq) return;
+      if (manualCountKeyRef.current !== countKey) return;
+      setPagination(prev => ({ ...prev, totalCountLoading: false }));
+      message.error(`统计总数失败: ${String(e?.message || e)}`);
+    }
+  }, [addSqlLog, runIsolatedQuery]);
+
+  const handleDuckDBCancelManualCount = useCallback(() => {
+    manualCountSeqRef.current++;
+    setPagination(prev => ({ ...prev, totalCountLoading: false, totalCountCancelled: true }));
+  }, []);
+
   const fetchData = useCallback(async (page = pagination.current, size = pagination.pageSize) => {
     const seq = ++fetchSeqRef.current;
     setLoading(true);
@@ -197,10 +367,24 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
             const isDuckDB = dbTypeLower === 'duckdb';
             const minExpectedTotal = hasMore ? offset + resultData.length + 1 : offset + resultData.length;
             if (derivedTotalKnown) countKeyRef.current = countKey;
+            latestConfigRef.current = config;
+            latestDbTypeRef.current = dbTypeLower;
+            latestDbNameRef.current = dbName;
+            latestCountSqlRef.current = countSql;
+            latestCountKeyRef.current = countKey;
 
             setPagination(prev => {
                 if (derivedTotalKnown) {
-                    return { ...prev, current: page, pageSize: size, total: derivedTotal, totalKnown: true };
+                    return {
+                        ...prev,
+                        current: page,
+                        pageSize: size,
+                        total: derivedTotal,
+                        totalKnown: true,
+                        totalApprox: false,
+                        totalCountLoading: false,
+                        totalCountCancelled: false,
+                    };
                 }
                 if (prev.totalKnown && countKeyRef.current === countKey) {
                     if (!isDuckDB) {
@@ -212,16 +396,38 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
                         return { ...prev, current: page, pageSize: size };
                     }
                 }
-                return { ...prev, current: page, pageSize: size, total: derivedTotal, totalKnown: false };
+                const keepManualCounting = prev.totalCountLoading && manualCountKeyRef.current === countKey;
+                if (isDuckDB && prev.totalApprox && duckdbApproxKeyRef.current === countKey && Number.isFinite(prev.total) && prev.total >= minExpectedTotal) {
+                    return {
+                        ...prev,
+                        current: page,
+                        pageSize: size,
+                        totalKnown: false,
+                        totalApprox: true,
+                        totalCountLoading: keepManualCounting,
+                        totalCountCancelled: false,
+                    };
+                }
+                return {
+                    ...prev,
+                    current: page,
+                    pageSize: size,
+                    total: derivedTotal,
+                    totalKnown: false,
+                    totalApprox: false,
+                    totalCountLoading: keepManualCounting,
+                    totalCountCancelled: keepManualCounting ? false : prev.totalCountCancelled,
+                };
             });
 
-            if (!derivedTotalKnown) {
+            const shouldRunAsyncCount = !derivedTotalKnown && !isDuckDB;
+            if (shouldRunAsyncCount) {
                 if (countKeyRef.current !== countKey) {
                     countKeyRef.current = countKey;
                     const countSeq = ++countSeqRef.current;
                     const countStart = Date.now();
                     // 大表 COUNT(*) 可能非常慢，且在部分运行时环境下会影响后续操作响应；
-                    // 这里为统计请求设置更短的超时，避免“后台统计”长期占用资源。
+                    // DuckDB 大文件场景下该统计会显著拖慢翻页，已禁用后台 COUNT。
                     const countConfig: any = { ...(config as any), timeout: 5 };
 
                     DBQuery(countConfig, dbName, countSql)
@@ -245,17 +451,20 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
                             if (!Array.isArray(resCount.data) || resCount.data.length === 0) return;
 
                             let total: number | null = null;
-                            if (dbTypeLower === 'duckdb') {
-                                total = parseTotalFromCountRow(resCount.data[0]);
-                            } else {
-                                const parsed = Number(resCount.data[0]?.['total']);
-                                if (Number.isFinite(parsed) && parsed >= 0) {
-                                    total = parsed;
-                                }
+                            const parsed = Number(resCount.data[0]?.['total']);
+                            if (Number.isFinite(parsed) && parsed >= 0) {
+                                total = parsed;
                             }
                             if (total === null) return;
 
-                            setPagination(prev => ({ ...prev, total, totalKnown: true }));
+                            setPagination(prev => ({
+                                ...prev,
+                                total,
+                                totalKnown: true,
+                                totalApprox: false,
+                                totalCountLoading: false,
+                                totalCountCancelled: false,
+                            }));
                         })
                         .catch(() => {
                             if (countSeqRef.current !== countSeq) return;
@@ -264,6 +473,50 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
                         });
                 }
             }
+
+            if (isDuckDB && !derivedTotalKnown && whereSQL.trim() === '' && duckdbApproxKeyRef.current !== countKey) {
+                duckdbApproxKeyRef.current = countKey;
+                const approxSeq = ++duckdbApproxSeqRef.current;
+                const { schemaName, pureTableName } = resolveDuckDBSchemaAndTable(dbName, tableName);
+                const escapedSchema = escapeSQLLiteral(schemaName);
+                const escapedTable = escapeSQLLiteral(pureTableName);
+                const approxConfig: any = { ...(config as any), timeout: 3 };
+                const approxSqlCandidates = [
+                    `SELECT estimated_size AS approx_total FROM duckdb_tables() WHERE schema_name='${escapedSchema}' AND table_name='${escapedTable}' LIMIT 1`,
+                    `SELECT estimated_size AS approx_total FROM duckdb_tables() WHERE table_name='${escapedTable}' ORDER BY CASE WHEN schema_name='${escapedSchema}' THEN 0 ELSE 1 END LIMIT 1`,
+                ];
+
+                (async () => {
+                    for (const approxSql of approxSqlCandidates) {
+                        try {
+                            const approxRes = await runIsolatedQuery(approxConfig, dbName, approxSql);
+                            if (duckdbApproxSeqRef.current !== approxSeq) return;
+                            if (countKeyRef.current !== countKey) return;
+                            if (!approxRes?.success || !Array.isArray(approxRes.data) || approxRes.data.length === 0) continue;
+
+                            const approxTotal = parseDuckDBApproxTotalRow(approxRes.data[0]);
+                            if (approxTotal === null) continue;
+                            if (!Number.isFinite(approxTotal) || approxTotal < minExpectedTotal) continue;
+
+                            setPagination(prev => {
+                                if (countKeyRef.current !== countKey) return prev;
+                                if (prev.totalKnown) return prev;
+                                return {
+                                    ...prev,
+                                    total: approxTotal,
+                                    totalKnown: false,
+                                    totalApprox: true,
+                                    totalCountCancelled: false,
+                                };
+                            });
+                            return;
+                        } catch {
+                            if (duckdbApproxSeqRef.current !== approxSeq) return;
+                            if (countKeyRef.current !== countKey) return;
+                        }
+                    }
+                })();
+            }
         } else {
             message.error(String(resData.message || '查询失败'));
         }
@@ -281,7 +534,7 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
         });
     }
     if (fetchSeqRef.current === seq) setLoading(false);
-  }, [connections, tab, sortInfo, filterConditions, pkColumns]); 
+  }, [connections, tab, sortInfo, filterConditions, pkColumns, runIsolatedQuery]); 
   // 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。
 
@@ -320,6 +573,8 @@ const DataViewer: React.FC<{ tab: TabData }> = ({ tab }) => {
           onSort={handleSort}
           onPageChange={handlePageChange}
           pagination={pagination}
+          onRequestTotalCount={currentConnType === 'duckdb' ? handleDuckDBManualCount : undefined}
+          onCancelTotalCount={currentConnType === 'duckdb' ? handleDuckDBCancelManualCount : undefined}
           showFilter={showFilter}
           onToggleFilter={handleToggleFilter}
           onApplyFilter={handleApplyFilter}

frontend/wailsjs/go/app/App.d.ts

@@ -34,6 +34,8 @@ export function DBGetTriggers(arg1:connection.ConnectionConfig,arg2:string,arg3:
 
 export function DBQuery(arg1:connection.ConnectionConfig,arg2:string,arg3:string):Promise<connection.QueryResult>;
 
+export function DBQueryIsolated(arg1:connection.ConnectionConfig,arg2:string,arg3:string):Promise<connection.QueryResult>;
+
 export function DBShowCreateTable(arg1:connection.ConnectionConfig,arg2:string,arg3:string):Promise<connection.QueryResult>;
 
 export function DataSync(arg1:sync.SyncConfig):Promise<sync.SyncResult>;

frontend/wailsjs/go/app/App.js

@@ -62,6 +62,10 @@ export function DBQuery(arg1, arg2, arg3) {
   return window['go']['app']['App']['DBQuery'](arg1, arg2, arg3);
 }
 
+export function DBQueryIsolated(arg1, arg2, arg3) {
+  return window['go']['app']['App']['DBQueryIsolated'](arg1, arg2, arg3);
+}
+
 export function DBShowCreateTable(arg1, arg2, arg3) {
   return window['go']['app']['App']['DBShowCreateTable'](arg1, arg2, arg3);
 }

internal/app/app.go

@@ -207,6 +207,32 @@ func (a *App) getDatabase(config connection.ConnectionConfig) (db.Database, erro
 	return a.getDatabaseWithPing(config, false)
 }
 
+func (a *App) openDatabaseIsolated(config connection.ConnectionConfig) (db.Database, error) {
+	effectiveConfig := applyGlobalProxyToConnection(config)
+	if supported, reason := db.DriverRuntimeSupportStatus(effectiveConfig.Type); !supported {
+		if strings.TrimSpace(reason) == "" {
+			reason = fmt.Sprintf("%s 驱动未启用，请先在驱动管理中安装启用", strings.TrimSpace(effectiveConfig.Type))
+		}
+		return nil, withLogHint{err: fmt.Errorf("%s", reason), logPath: logger.Path()}
+	}
+
+	dbInst, err := db.NewDatabase(effectiveConfig.Type)
+	if err != nil {
+		return nil, err
+	}
+
+	connectConfig, proxyErr := resolveDialConfigWithProxy(effectiveConfig)
+	if proxyErr != nil {
+		_ = dbInst.Close()
+		return nil, wrapConnectError(effectiveConfig, proxyErr)
+	}
+	if err := dbInst.Connect(connectConfig); err != nil {
+		_ = dbInst.Close()
+		return nil, wrapConnectError(effectiveConfig, err)
+	}
+	return dbInst, nil
+}
+
 func (a *App) getDatabaseWithPing(config connection.ConnectionConfig, forcePing bool) (db.Database, error) {
 	effectiveConfig := applyGlobalProxyToConnection(config)
 

internal/app/methods_db.go

@@ -7,6 +7,7 @@ import (
 	"time"
 
 	"GoNavi-Wails/internal/connection"
+	"GoNavi-Wails/internal/db"
 	"GoNavi-Wails/internal/logger"
 	"GoNavi-Wails/internal/utils"
 )
@@ -112,16 +113,39 @@ func resolveDDLDBType(config connection.ConnectionConfig) string {
 
 	driver := strings.ToLower(strings.TrimSpace(config.Driver))
 	switch driver {
-	case "postgresql":
+	case "postgresql", "postgres", "pg", "pq", "pgx":
 		return "postgres"
-	case "dm":
+	case "dm", "dameng", "dm8":
 		return "dameng"
-	case "sqlite3":
+	case "sqlite3", "sqlite":
 		return "sqlite"
 	case "sphinxql":
 		return "sphinx"
 	case "diros", "doris":
 		return "diros"
+	case "kingbase", "kingbase8", "kingbasees", "kingbasev8":
+		return "kingbase"
+	case "highgo":
+		return "highgo"
+	case "vastbase":
+		return "vastbase"
+	}
+
+	switch {
+	case strings.Contains(driver, "postgres"):
+		return "postgres"
+	case strings.Contains(driver, "kingbase"):
+		return "kingbase"
+	case strings.Contains(driver, "highgo"):
+		return "highgo"
+	case strings.Contains(driver, "vastbase"):
+		return "vastbase"
+	case strings.Contains(driver, "sqlite"):
+		return "sqlite"
+	case strings.Contains(driver, "sphinx"):
+		return "sphinx"
+	case strings.Contains(driver, "diros"), strings.Contains(driver, "doris"):
+		return "diros"
 	default:
 		return driver
 	}
@@ -406,6 +430,66 @@ func (a *App) DBQuery(config connection.ConnectionConfig, dbName string, query s
 	}
 }
 
+func (a *App) DBQueryIsolated(config connection.ConnectionConfig, dbName string, query string) connection.QueryResult {
+	runConfig := normalizeRunConfig(config, dbName)
+
+	dbInst, err := a.openDatabaseIsolated(runConfig)
+	if err != nil {
+		logger.Error(err, "DBQueryIsolated 获取连接失败：%s", formatConnSummary(runConfig))
+		return connection.QueryResult{Success: false, Message: err.Error()}
+	}
+	defer func() {
+		if closeErr := dbInst.Close(); closeErr != nil {
+			logger.Error(closeErr, "DBQueryIsolated 关闭临时连接失败：%s", formatConnSummary(runConfig))
+		}
+	}()
+
+	query = sanitizeSQLForPgLike(runConfig.Type, query)
+	timeoutSeconds := runConfig.Timeout
+	if timeoutSeconds <= 0 {
+		timeoutSeconds = 30
+	}
+	ctx, cancel := utils.ContextWithTimeout(time.Duration(timeoutSeconds) * time.Second)
+	defer cancel()
+
+	lowerQuery := strings.TrimSpace(strings.ToLower(query))
+	isReadQuery := strings.HasPrefix(lowerQuery, "select") || strings.HasPrefix(lowerQuery, "show") || strings.HasPrefix(lowerQuery, "describe") || strings.HasPrefix(lowerQuery, "explain")
+	if !isReadQuery && strings.ToLower(strings.TrimSpace(runConfig.Type)) == "mongodb" && strings.HasPrefix(strings.TrimSpace(query), "{") {
+		isReadQuery = true
+	}
+
+	if isReadQuery {
+		var data []map[string]interface{}
+		var columns []string
+		if q, ok := dbInst.(interface {
+			QueryContext(context.Context, string) ([]map[string]interface{}, []string, error)
+		}); ok {
+			data, columns, err = q.QueryContext(ctx, query)
+		} else {
+			data, columns, err = dbInst.Query(query)
+		}
+		if err != nil {
+			logger.Error(err, "DBQueryIsolated 查询失败：%s SQL片段=%q", formatConnSummary(runConfig), sqlSnippet(query))
+			return connection.QueryResult{Success: false, Message: err.Error()}
+		}
+		return connection.QueryResult{Success: true, Data: data, Fields: columns}
+	}
+
+	var affected int64
+	if e, ok := dbInst.(interface {
+		ExecContext(context.Context, string) (int64, error)
+	}); ok {
+		affected, err = e.ExecContext(ctx, query)
+	} else {
+		affected, err = dbInst.Exec(query)
+	}
+	if err != nil {
+		logger.Error(err, "DBQueryIsolated 执行失败：%s SQL片段=%q", formatConnSummary(runConfig), sqlSnippet(query))
+		return connection.QueryResult{Success: false, Message: err.Error()}
+	}
+	return connection.QueryResult{Success: true, Data: map[string]int64{"affectedRows": affected}}
+}
+
 func sqlSnippet(query string) string {
 	q := strings.TrimSpace(query)
 	const max = 200
@@ -460,8 +544,8 @@ func (a *App) DBGetTables(config connection.ConnectionConfig, dbName string) con
 }
 
 func (a *App) DBShowCreateTable(config connection.ConnectionConfig, dbName string, tableName string) connection.QueryResult {
-	runConfig := normalizeRunConfig(config, dbName)
 	dbType := resolveDDLDBType(config)
+	runConfig := buildRunConfigForDDL(config, dbType, dbName)
 
 	dbInst, err := a.getDatabase(runConfig)
 	if err != nil {
@@ -469,35 +553,65 @@ func (a *App) DBShowCreateTable(config connection.ConnectionConfig, dbName strin
 		return connection.QueryResult{Success: false, Message: err.Error()}
 	}
 
-	schemaName, pureTableName := normalizeSchemaAndTable(config, dbName, tableName)
-	sqlStr, err := dbInst.GetCreateStatement(schemaName, pureTableName)
+	sqlStr, err := resolveCreateStatementWithFallback(dbInst, config, dbName, tableName)
 	if err != nil {
 		logger.Error(err, "DBShowCreateTable 获取建表语句失败：%s 表=%s", formatConnSummary(runConfig), tableName)
 		return connection.QueryResult{Success: false, Message: err.Error()}
 	}
-	if shouldFallbackCreateStatement(dbType, sqlStr) {
-		columns, colErr := dbInst.GetColumns(schemaName, pureTableName)
-		if colErr != nil {
-			logger.Error(colErr, "DBShowCreateTable 兜底加载字段失败：%s 表=%s", formatConnSummary(runConfig), tableName)
-			return connection.QueryResult{Success: false, Message: colErr.Error()}
-		}
-		fallbackDDL, buildErr := buildFallbackCreateStatement(dbType, schemaName, pureTableName, columns)
-		if buildErr != nil {
-			logger.Error(buildErr, "DBShowCreateTable 兜底生成 DDL 失败：%s 表=%s", formatConnSummary(runConfig), tableName)
-			return connection.QueryResult{Success: false, Message: buildErr.Error()}
-		}
-		sqlStr = fallbackDDL
-	}
 
 	return connection.QueryResult{Success: true, Data: sqlStr}
 }
 
-func shouldFallbackCreateStatement(dbType string, ddl string) bool {
+func resolveCreateStatementWithFallback(dbInst db.Database, config connection.ConnectionConfig, dbName string, tableName string) (string, error) {
+	dbType := resolveDDLDBType(config)
+	schemaName, pureTableName := normalizeSchemaAndTableByType(dbType, dbName, tableName)
+	if pureTableName == "" {
+		return "", fmt.Errorf("表名不能为空")
+	}
+
+	sqlStr, sourceErr := dbInst.GetCreateStatement(schemaName, pureTableName)
+	if sourceErr == nil && !shouldFallbackCreateStatement(dbType, sqlStr) {
+		return sqlStr, nil
+	}
+
+	if !supportsCreateStatementFallback(dbType) {
+		if sourceErr != nil {
+			return "", sourceErr
+		}
+		return sqlStr, nil
+	}
+
+	columns, colErr := dbInst.GetColumns(schemaName, pureTableName)
+	if colErr != nil {
+		if sourceErr != nil {
+			return "", sourceErr
+		}
+		return "", colErr
+	}
+
+	fallbackDDL, buildErr := buildFallbackCreateStatement(dbType, schemaName, pureTableName, columns)
+	if buildErr != nil {
+		if sourceErr != nil {
+			return "", sourceErr
+		}
+		return "", buildErr
+	}
+	return fallbackDDL, nil
+}
+
+func supportsCreateStatementFallback(dbType string) bool {
 	switch dbType {
 	case "postgres", "kingbase", "highgo", "vastbase":
+		return true
 	default:
 		return false
 	}
+}
+
+func shouldFallbackCreateStatement(dbType string, ddl string) bool {
+	if !supportsCreateStatementFallback(dbType) {
+		return false
+	}
 
 	trimmed := strings.TrimSpace(ddl)
 	if trimmed == "" {

internal/app/methods_db_create_statement_test.go

@@ -0,0 +1,174 @@
+package app
+
+import (
+	"errors"
+	"strings"
+	"testing"
+
+	"GoNavi-Wails/internal/connection"
+)
+
+type fakeCreateStatementDB struct {
+	createSQL  string
+	createErr  error
+	columns    []connection.ColumnDefinition
+	columnsErr error
+
+	createSchema string
+	createTable  string
+	colsSchema   string
+	colsTable    string
+}
+
+func (f *fakeCreateStatementDB) Connect(config connection.ConnectionConfig) error { return nil }
+func (f *fakeCreateStatementDB) Close() error                                     { return nil }
+func (f *fakeCreateStatementDB) Ping() error                                      { return nil }
+func (f *fakeCreateStatementDB) Query(query string) ([]map[string]interface{}, []string, error) {
+	return nil, nil, nil
+}
+func (f *fakeCreateStatementDB) Exec(query string) (int64, error)          { return 0, nil }
+func (f *fakeCreateStatementDB) GetDatabases() ([]string, error)           { return nil, nil }
+func (f *fakeCreateStatementDB) GetTables(dbName string) ([]string, error) { return nil, nil }
+func (f *fakeCreateStatementDB) GetCreateStatement(dbName, tableName string) (string, error) {
+	f.createSchema = dbName
+	f.createTable = tableName
+	return f.createSQL, f.createErr
+}
+func (f *fakeCreateStatementDB) GetColumns(dbName, tableName string) ([]connection.ColumnDefinition, error) {
+	f.colsSchema = dbName
+	f.colsTable = tableName
+	return f.columns, f.columnsErr
+}
+func (f *fakeCreateStatementDB) GetAllColumns(dbName string) ([]connection.ColumnDefinitionWithTable, error) {
+	return nil, nil
+}
+func (f *fakeCreateStatementDB) GetIndexes(dbName, tableName string) ([]connection.IndexDefinition, error) {
+	return nil, nil
+}
+func (f *fakeCreateStatementDB) GetForeignKeys(dbName, tableName string) ([]connection.ForeignKeyDefinition, error) {
+	return nil, nil
+}
+func (f *fakeCreateStatementDB) GetTriggers(dbName, tableName string) ([]connection.TriggerDefinition, error) {
+	return nil, nil
+}
+
+func TestResolveDDLDBType_CustomDriverAlias(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		name   string
+		driver string
+		want   string
+	}{
+		{name: "postgresql alias", driver: "postgresql", want: "postgres"},
+		{name: "pgx alias", driver: "pgx", want: "postgres"},
+		{name: "kingbase8 alias", driver: "kingbase8", want: "kingbase"},
+		{name: "kingbase contains alias", driver: "kingbasees", want: "kingbase"},
+		{name: "dm alias", driver: "dm8", want: "dameng"},
+		{name: "sqlite alias", driver: "sqlite3", want: "sqlite"},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+			cfg := connection.ConnectionConfig{Type: "custom", Driver: tc.driver}
+			if got := resolveDDLDBType(cfg); got != tc.want {
+				t.Fatalf("resolveDDLDBType() mismatch, want=%q got=%q", tc.want, got)
+			}
+		})
+	}
+}
+
+func TestResolveCreateStatementWithFallback_CustomKingbaseUsesPublicSchema(t *testing.T) {
+	t.Parallel()
+
+	dbInst := &fakeCreateStatementDB{
+		createSQL: "SHOW CREATE TABLE not directly supported in Kingbase/Postgres via SQL",
+		columns: []connection.ColumnDefinition{
+			{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
+		},
+	}
+
+	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{
+		Type:   "custom",
+		Driver: "kingbase8",
+	}, "demo_db", "orders")
+	if err != nil {
+		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
+	}
+	if dbInst.createSchema != "public" || dbInst.colsSchema != "public" {
+		t.Fatalf("expected fallback schema public, got create=%q columns=%q", dbInst.createSchema, dbInst.colsSchema)
+	}
+	if !strings.Contains(ddl, `CREATE TABLE "public"."orders"`) {
+		t.Fatalf("expected fallback DDL with public schema, got: %s", ddl)
+	}
+}
+
+func TestResolveCreateStatementWithFallback_KeepQualifiedSchema(t *testing.T) {
+	t.Parallel()
+
+	dbInst := &fakeCreateStatementDB{
+		createSQL: "-- SHOW CREATE TABLE not fully supported for PostgreSQL in this MVP.",
+		columns: []connection.ColumnDefinition{
+			{Name: "id", Type: "integer", Nullable: "NO", Key: "PRI"},
+		},
+	}
+
+	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{
+		Type:   "custom",
+		Driver: "postgresql",
+	}, "demo_db", "sales.orders")
+	if err != nil {
+		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
+	}
+	if dbInst.createSchema != "sales" || dbInst.colsSchema != "sales" {
+		t.Fatalf("expected schema sales, got create=%q columns=%q", dbInst.createSchema, dbInst.colsSchema)
+	}
+	if !strings.Contains(ddl, `CREATE TABLE "sales"."orders"`) {
+		t.Fatalf("expected fallback DDL with sales schema, got: %s", ddl)
+	}
+}
+
+func TestResolveCreateStatementWithFallback_NoFallbackForMySQL(t *testing.T) {
+	t.Parallel()
+
+	dbInst := &fakeCreateStatementDB{
+		createSQL:  "SHOW CREATE TABLE not directly supported in Kingbase/Postgres via SQL",
+		columnsErr: errors.New("should not be called"),
+	}
+
+	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{
+		Type: "mysql",
+	}, "demo_db", "orders")
+	if err != nil {
+		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
+	}
+	if ddl != dbInst.createSQL {
+		t.Fatalf("expected original ddl for mysql, got: %s", ddl)
+	}
+	if dbInst.colsTable != "" {
+		t.Fatalf("mysql path should not call GetColumns, got table=%q", dbInst.colsTable)
+	}
+}
+
+func TestResolveCreateStatementWithFallback_FallbackWhenCreateStatementError(t *testing.T) {
+	t.Parallel()
+
+	dbInst := &fakeCreateStatementDB{
+		createErr: errors.New("statement unsupported"),
+		columns: []connection.ColumnDefinition{
+			{Name: "id", Type: "bigint", Nullable: "NO", Key: "PRI"},
+		},
+	}
+
+	ddl, err := resolveCreateStatementWithFallback(dbInst, connection.ConnectionConfig{
+		Type: "postgres",
+	}, "demo_db", "orders")
+	if err != nil {
+		t.Fatalf("resolveCreateStatementWithFallback() unexpected error: %v", err)
+	}
+	if !strings.Contains(ddl, `CREATE TABLE "public"."orders"`) {
+		t.Fatalf("expected fallback DDL for postgres error path, got: %s", ddl)
+	}
+}

internal/app/methods_file.go

@@ -1291,7 +1291,7 @@ func dumpTableSQL(
 				createSQL = ddl
 			}
 		} else {
-			ddl, err := dbInst.GetCreateStatement(schemaName, pureTableName)
+			ddl, err := resolveCreateStatementWithFallback(dbInst, config, dbName, tableName)
 			if err != nil {
 				if viewDDL, ok := tryGetViewCreateStatement(dbInst, config, dbName, schemaName, pureTableName); ok {
 					createSQL = viewDDL