QueryaHub · ZhuchkaTriplesix · Sep 6, 2026 · Sep 6, 2026
diff --git a/lib/core/database/table_mutation_engine.dart b/lib/core/database/table_mutation_engine.dart
@@ -183,8 +183,7 @@ abstract final class TableMutationEngine {
 
       if (_isTextType(dataTypeName)) {
         // String columns: preserve literal 'NULL' or 'null' as a text string
-        final escaped = value.replaceAll("'", "''");
-        return "'$escaped'";
+        return _formatStringLiteral(value, dialect);
       }
 
       if (_isBoolType(dataTypeName)) {
@@ -216,8 +215,7 @@ abstract final class TableMutationEngine {
     // Fallback heuristic:
     // Leading zeros with more digits (e.g. '01234', '007') are preserved as strings
     if (RegExp(r'^0\d+$').hasMatch(trimmed)) {
-      final escaped = value.replaceAll("'", "''");
-      return "'$escaped'";
+      return _formatStringLiteral(value, dialect);
     }
 
     // Number literals (integer or floating point, e.g. '123', '0', '0.45', '-5.2')
@@ -233,8 +231,16 @@ abstract final class TableMutationEngine {
       return dialect == SqlDialect.sqlite ? '0' : 'FALSE';
     }
 
-    // String literal with single quote escape
-    final escaped = value.replaceAll("'", "''");
+    // String literal with single quote escape and MySQL backslash escape
+    return _formatStringLiteral(value, dialect);
+  }
+
+  static String _formatStringLiteral(String value, SqlDialect dialect) {
+    var escaped = value;
+    if (dialect == SqlDialect.mysql) {
+      escaped = escaped.replaceAll(r'\', r'\\');
+    }
+    escaped = escaped.replaceAll("'", "''");
     return "'$escaped'";
   }
 

diff --git a/lib/features/workspace/result_grid_view.dart b/lib/features/workspace/result_grid_view.dart
@@ -339,7 +339,8 @@ class ResultGridSelection {
     if (columns != null && columns.isNotEmpty) {
       final headerCells = <String>[];
       for (var c = startColumn; c <= endColumn; c++) {
-        headerCells.add(c < columns.length ? columns[c] : '');
+        final col = c < columns.length ? columns[c] : '';
+        headerCells.add(_escapeTsv(col));
       }
       buffer.writeln(headerCells.join('\t'));
     }
@@ -348,7 +349,8 @@ class ResultGridSelection {
       final rowData = rows[r];
       final cells = <String>[];
       for (var c = startColumn; c <= endColumn; c++) {
-        cells.add(c < rowData.length ? rowData[c] : '');
+        final val = c < rowData.length ? rowData[c] : '';
+        cells.add(_escapeTsv(val));
       }
       buffer.writeln(cells.join('\t'));
     }
@@ -395,6 +397,9 @@ class ResultGridSelection {
         final val = c < rowData.length ? rowData[c] : '';
         if (val == 'NULL') {
           map[colName] = null;
+        } else if (RegExp(r'^0\d+$').hasMatch(val.trim())) {
+          // Preserve numeric strings with leading zeros (e.g. '01234', '007')
+          map[colName] = val;
         } else if (int.tryParse(val) != null) {
           map[colName] = int.parse(val);
         } else if (double.tryParse(val) != null) {
@@ -415,6 +420,13 @@ class ResultGridSelection {
     return const JsonEncoder.withIndent('  ').convert(result);
   }
 
+  static String _escapeTsv(String val) {
+    if (val.contains('\t') || val.contains('\n') || val.contains('\r') || val.contains('"')) {
+      return '"${val.replaceAll('"', '""')}"';
+    }
+    return val;
+  }
+
   static String _escapeCsv(String val) {
     if (val.contains(',') || val.contains('"') || val.contains('\n') || val.contains('\r')) {
       return '"${val.replaceAll('"', '""')}"';
@@ -568,6 +580,7 @@ class VirtualResultGrid extends material.StatefulWidget {
     required this.columns,
     required this.rows,
     this.stagingBuffer,
+    this.rowIndicesMapping,
     this.onRowSelected,
     this.onSelectionValuesChanged,
     this.onCellFocused,
@@ -577,6 +590,7 @@ class VirtualResultGrid extends material.StatefulWidget {
   final List<String> columns;
   final List<List<String>> rows;
   final DataGridStagingBuffer? stagingBuffer;
+  final List<int>? rowIndicesMapping;
   final material.ValueChanged<int?>? onRowSelected;
   final material.ValueChanged<List<String>>? onSelectionValuesChanged;
   final void Function(String columnName, String cellValue, int rowIndex)? onCellFocused;
@@ -638,7 +652,8 @@ class _VirtualResultGridState extends material.State<VirtualResultGrid> {
     }
     if (oldWidget.columns != widget.columns ||
         oldWidget.rows != widget.rows ||
-        oldWidget.stagingBuffer != widget.stagingBuffer) {
+        oldWidget.stagingBuffer != widget.stagingBuffer ||
+        oldWidget.rowIndicesMapping != widget.rowIndicesMapping) {
       _widthsNeedUpdate = true;
       if (oldWidget.columns != widget.columns) {
         _userHasResized = false;
@@ -810,7 +825,7 @@ class _VirtualResultGridState extends material.State<VirtualResultGrid> {
       rowIndex: row,
     );
     if (result != null && widget.stagingBuffer != null) {
-      widget.stagingBuffer!.setCell(row, column, result);
+      widget.stagingBuffer!.setCell(_toModelRowIndex(row), column, result);
     }
   }
 
@@ -883,22 +898,37 @@ class _VirtualResultGridState extends material.State<VirtualResultGrid> {
     });
   }
 
-  List<List<String>> get _baseRows =>
-      widget.stagingBuffer?.effectiveRows ?? widget.rows;
+  List<List<String>> get _baseRows {
+    if (widget.rowIndicesMapping != null) {
+      return widget.rows;
+    }
+    return widget.stagingBuffer?.effectiveRows ?? widget.rows;
+  }
 
   void _updateSortedRows() {
     final rows = _baseRows;
     if (_sortColumnIndex == null || _sortOrder == null) {
       _sortedRows = rows;
-      _sortedToModelIndices = List<int>.generate(rows.length, (i) => i, growable: false);
+      if (widget.rowIndicesMapping != null) {
+        _sortedToModelIndices = List<int>.from(widget.rowIndicesMapping!);
+      } else {
+        _sortedToModelIndices = List<int>.generate(rows.length, (i) => i, growable: false);
+      }
     } else {
       final sortedData = sortResultGridRowsWithIndices(
         rows: rows,
         columnIndex: _sortColumnIndex!,
         order: _sortOrder!,
       );
       _sortedRows = sortedData.rows;
-      _sortedToModelIndices = sortedData.sortedToModelIndices;
+      if (widget.rowIndicesMapping != null) {
+        final mapping = widget.rowIndicesMapping!;
+        _sortedToModelIndices = sortedData.sortedToModelIndices
+            .map((i) => i < mapping.length ? mapping[i] : i)
+            .toList(growable: false);
+      } else {
+        _sortedToModelIndices = sortedData.sortedToModelIndices;
+      }
     }
   }
 
@@ -1387,31 +1417,31 @@ class _VirtualResultGridState extends material.State<VirtualResultGrid> {
           control: true,
         ): () {
           if (widget.stagingBuffer != null && _selection != null) {
-            widget.stagingBuffer!.toggleDeleteRow(_selection!.startRow);
+            widget.stagingBuffer!.toggleDeleteRow(_toModelRowIndex(_selection!.startRow));
           }
         },
         const material.SingleActivator(
           LogicalKeyboardKey.backspace,
           meta: true,
         ): () {
           if (widget.stagingBuffer != null && _selection != null) {
-            widget.stagingBuffer!.toggleDeleteRow(_selection!.startRow);
+            widget.stagingBuffer!.toggleDeleteRow(_toModelRowIndex(_selection!.startRow));
           }
         },
         const material.SingleActivator(
           LogicalKeyboardKey.keyZ,
           control: true,
         ): () {
           if (widget.stagingBuffer != null && _selection != null) {
-            widget.stagingBuffer!.revertRow(_selection!.startRow);
+            widget.stagingBuffer!.revertRow(_toModelRowIndex(_selection!.startRow));
           }
         },
         const material.SingleActivator(
           LogicalKeyboardKey.keyZ,
           meta: true,
         ): () {
           if (widget.stagingBuffer != null && _selection != null) {
-            widget.stagingBuffer!.revertRow(_selection!.startRow);
+            widget.stagingBuffer!.revertRow(_toModelRowIndex(_selection!.startRow));
           }
         },
         const material.SingleActivator(

diff --git a/lib/features/workspace/results_tab.dart b/lib/features/workspace/results_tab.dart
@@ -72,6 +72,7 @@ class _ResultsTabState extends material.State<ResultsTab> {
   List<String>? _memoColumns;
   List<List<String>>? _memoEffectiveRows;
   List<List<String>> _cachedFilteredRows = const [];
+  List<int>? _cachedFilteredIndices;
 
   List<List<String>> _getFilteredRows(
     List<List<String>> effectiveRows,
@@ -89,14 +90,16 @@ class _ResultsTabState extends material.State<ResultsTab> {
       rows: effectiveRows,
     );
 
-    final filteredRows = filteredIndices.length == effectiveRows.length
+    final isFiltered = filteredIndices.length != effectiveRows.length;
+    final filteredRows = !isFiltered
         ? effectiveRows
         : filteredIndices.map((i) => effectiveRows[i]).toList();
 
     _memoFilterText = _filterText;
     _memoEffectiveRows = effectiveRows;
     _memoColumns = columns;
     _cachedFilteredRows = filteredRows;
+    _cachedFilteredIndices = isFiltered ? filteredIndices : null;
 
     return filteredRows;
   }
@@ -106,6 +109,7 @@ class _ResultsTabState extends material.State<ResultsTab> {
     _memoColumns = null;
     _memoEffectiveRows = null;
     _cachedFilteredRows = const [];
+    _cachedFilteredIndices = null;
     super.dispose();
   }
 
@@ -387,6 +391,7 @@ class _ResultsTabState extends material.State<ResultsTab> {
                         columns: widget.columns,
                         rows: filteredRows,
                         stagingBuffer: widget.stagingBuffer,
+                        rowIndicesMapping: _cachedFilteredIndices,
                         onRowSelected: (row) => setState(() => _selectedRowIndex = row),
                         onSelectionValuesChanged: (values) {
                           if (values.isEmpty) {

diff --git a/lib/features/workspace/sql_query_tab_session.dart b/lib/features/workspace/sql_query_tab_session.dart
@@ -35,5 +35,6 @@ class SqlQueryTabSession {
   void dispose() {
     controller.dispose();
     topFraction.dispose();
+    stagingBuffer?.dispose();
   }
 }
diff --git a/test/core/database/table_mutation_engine_test.dart b/test/core/database/table_mutation_engine_test.dart
@@ -323,5 +323,34 @@ void main() {
         'NULL',
       );
     });
+
+    test('escapes backslashes in MySQL dialect string literals', () {
+      // Path with backslashes in MySQL
+      expect(
+        TableMutationEngine.formatLiteral(
+          r'C:\Program Files\App\',
+          SqlDialect.mysql,
+        ),
+        r"'C:\\Program Files\\App\\'",
+      );
+
+      // Trailing backslash with single quote
+      expect(
+        TableMutationEngine.formatLiteral(
+          r"test\'end",
+          SqlDialect.mysql,
+        ),
+        r"'test\\''end'",
+      );
+
+      // Postgres does not escape backslashes with double backslash
+      expect(
+        TableMutationEngine.formatLiteral(
+          r'C:\Program Files\',
+          SqlDialect.postgres,
+        ),
+        r"'C:\Program Files\'",
+      );
+    });
   });
 }
diff --git a/test/features/workspace/data_grid_context_menu_test.dart b/test/features/workspace/data_grid_context_menu_test.dart
@@ -134,6 +134,45 @@ void main() {
       expect(decoded[1]['name'], equals('Bob, Jr.'));
       expect(decoded[1]['score'], equals(80));
     });
+
+    test('toTsv escapes cells with tabs, newlines, and quotes', () {
+      final rowsWithSpecialChars = [
+        ['1', 'Line1\nLine2', 'Tab\there', 'Quoted "value"'],
+      ];
+      const sel = ResultGridSelection(
+        startRow: 0,
+        startColumn: 0,
+        endRow: 0,
+        endColumn: 3,
+      );
+
+      final tsv = sel.toTsv(rowsWithSpecialChars);
+      expect(
+        tsv,
+        equals('1\t"Line1\nLine2"\t"Tab\there"\t"Quoted ""value"""'),
+      );
+    });
+
+    test('toJson preserves strings with leading zeros', () {
+      final rowsWithLeadingZeros = [
+        ['007', '01234', '0', '42'],
+      ];
+      const cols = ['agent_id', 'zip', 'zero_num', 'plain_num'];
+      const sel = ResultGridSelection(
+        startRow: 0,
+        startColumn: 0,
+        endRow: 0,
+        endColumn: 3,
+      );
+
+      final jsonStr = sel.toJson(cols, rowsWithLeadingZeros);
+      final decoded = jsonDecode(jsonStr) as Map<String, dynamic>;
+
+      expect(decoded['agent_id'], equals('007'));
+      expect(decoded['zip'], equals('01234'));
+      expect(decoded['zero_num'], equals(0));
+      expect(decoded['plain_num'], equals(42));
+    });
   });
 
   group('VirtualResultGrid Non-Destructive Secondary Click', () {

diff --git a/test/features/workspace/results_tab_test.dart b/test/features/workspace/results_tab_test.dart
@@ -999,6 +999,73 @@ void main() {
       expect(find.text('Bob'), findsNothing);
       expect(find.text('2 of 3 rows'), findsOneWidget);
     });
+
+    testWidgets('filters rows and mutates correct underlying row when StagingBuffer is attached', (tester) async {
+      final buffer = DataGridStagingBuffer(
+        columns: const ['id', 'name', 'department'],
+        rows: const [
+          ['1', 'Alice', 'Engineering'],
+          ['2', 'Bob', 'Marketing'],
+          ['3', 'Charlie', 'Engineering'],
+        ],
+      );
+
+      await tester.pumpWidget(
+        resultsShell(
+          child: material.Scaffold(
+            body: material.SizedBox(
+              width: 800,
+              height: 600,
+              child: ResultsTab(
+                columns: const ['id', 'name', 'department'],
+                rows: buffer.effectiveRows,
+                stagingBuffer: buffer,
+              ),
+            ),
+          ),
+        ),
+      );
+      await tester.pumpAndSettle();
+
+      expect(find.text('Alice'), findsOneWidget);
+      expect(find.text('Bob'), findsOneWidget);
+      expect(find.text('Charlie'), findsOneWidget);
+
+      // Open quick filter bar
+      await tester.tap(find.byTooltip('Toggle Quick Filter'));
+      await tester.pumpAndSettle();
+
+      // Enter filter 'Bob'
+      await tester.enterText(find.byType(material.TextField), 'Bob');
+      await tester.pumpAndSettle();
+
+      // Only Bob should be displayed in the grid
+      final bobGridCell = find.descendant(
+        of: find.byType(VirtualResultGrid),
+        matching: find.text('Bob'),
+      );
+      expect(bobGridCell, findsOneWidget);
+      expect(find.text('Alice'), findsNothing);
+      expect(find.text('Charlie'), findsNothing);
+
+      // Tap Bob cell to select the row
+      await tester.tap(bobGridCell);
+      await tester.pump(const Duration(milliseconds: 350));
+      await tester.pumpAndSettle();
+
+      // Tap 'Delete Row' on the staging toolbar
+      final deleteBtn = find.text('Delete Row');
+      expect(deleteBtn, findsOneWidget);
+      await tester.tap(deleteBtn);
+      await tester.pumpAndSettle();
+
+      // Verify that underlying buffer index 1 (Bob's row) was marked deleted, NOT Alice (index 0)
+      expect(buffer.getRowStatus(1), equals(StagedRowStatus.deleted));
+      expect(buffer.getRowStatus(0), equals(StagedRowStatus.unchanged));
+      expect(buffer.getRowStatus(2), equals(StagedRowStatus.unchanged));
+
+      buffer.dispose();
+    });
   });
 }