fix(grid): clear primary key columns when duplicating a row in staging buffer (#888)

lib/features/extensions/extension_table_view.dart

@@ -315,6 +315,7 @@ class _ExtensionTableViewState extends material.State<ExtensionTableView> {
           columns: _columns,
           rows: _rows,
           enabled: editingEnabled,
+          primaryKeys: _primaryKeys,
         );
         _updateStatusLine();
       });

lib/features/mysql/mysql_sql_workspace.dart

@@ -424,7 +424,11 @@ class _MysqlSqlWorkspaceState extends material.State<MysqlSqlWorkspace> {
         session.resultGridColumnDataTypes = types;
         session.stagingBuffer?.dispose();
         session.stagingBuffer = canSave
-            ? DataGridStagingBuffer(columns: cols, rows: outRows)
+            ? DataGridStagingBuffer(
+                columns: cols,
+                rows: outRows,
+                primaryKeys: pks,
+              )
             : null;
         if (cols.isEmpty && outRows.isEmpty) {
           session.statusLine = affected != null
@@ -543,7 +547,11 @@ class _MysqlSqlWorkspaceState extends material.State<MysqlSqlWorkspace> {
       setState(() {
         session.rows = newRows;
         session.stagingBuffer =
-            DataGridStagingBuffer(columns: session.columns, rows: session.rows);
+            DataGridStagingBuffer(
+          columns: session.columns,
+          rows: session.rows,
+          primaryKeys: session.resultGridPrimaryKeys,
+        );
         session.savingChanges = false;
       });
     } catch (e) {

lib/features/mysql/mysql_table_view.dart

@@ -146,6 +146,7 @@ class _MysqlTableViewState extends material.State<MysqlTableView> {
         columns: _columnNames,
         rows: _rows,
         enabled: _editingEnabled,
+        primaryKeys: _primaryKeys,
       );
     }
     if (mounted) setState(() {});
@@ -300,6 +301,7 @@ class _MysqlTableViewState extends material.State<MysqlTableView> {
       columns: columns,
       rows: rows,
       enabled: _editingEnabled,
+      primaryKeys: _primaryKeys,
     );
   }
 
@@ -585,6 +587,7 @@ class _MysqlTableViewState extends material.State<MysqlTableView> {
           columns: _columnNames,
           rows: newRows,
           enabled: _editingEnabled,
+          primaryKeys: _primaryKeys,
         );
         _isSaving = false;
       });

lib/features/postgresql/postgres_sql_workspace.dart

@@ -545,7 +545,11 @@ class _PostgresSqlWorkspaceState extends material.State<PostgresSqlWorkspace> {
         session.resultGridColumnDataTypes = types;
         session.stagingBuffer?.dispose();
         session.stagingBuffer = canSave
-            ? DataGridStagingBuffer(columns: cols, rows: outRows)
+            ? DataGridStagingBuffer(
+                columns: cols,
+                rows: outRows,
+                primaryKeys: pks,
+              )
             : null;
         if (cols.isEmpty && outRows.isEmpty) {
           session.statusLine =
@@ -671,7 +675,11 @@ class _PostgresSqlWorkspaceState extends material.State<PostgresSqlWorkspace> {
       setState(() {
         session.rows = newRows;
         session.stagingBuffer =
-            DataGridStagingBuffer(columns: session.columns, rows: session.rows);
+            DataGridStagingBuffer(
+          columns: session.columns,
+          rows: session.rows,
+          primaryKeys: session.resultGridPrimaryKeys,
+        );
         session.savingChanges = false;
       });
       await _refreshTxStatus();

lib/features/postgresql/postgres_table_view.dart

@@ -256,6 +256,7 @@ class _PostgresTableViewState extends material.State<PostgresTableView> {
       columns: columns,
       rows: rows,
       enabled: _editingEnabled,
+      primaryKeys: _primaryKeys,
     );
   }
 
@@ -606,6 +607,7 @@ class _PostgresTableViewState extends material.State<PostgresTableView> {
           columns: _columnNames,
           rows: newRows,
           enabled: _editingEnabled,
+          primaryKeys: _primaryKeys,
         );
         _isSaving = false;
       });

lib/features/sqlite/sqlite_sql_workspace.dart

@@ -395,7 +395,11 @@ class _SqliteSqlWorkspaceState extends material.State<SqliteSqlWorkspace> {
         session.resultGridColumnDataTypes = types;
         session.stagingBuffer?.dispose();
         session.stagingBuffer = canSave
-            ? DataGridStagingBuffer(columns: cols, rows: outRows)
+            ? DataGridStagingBuffer(
+                columns: cols,
+                rows: outRows,
+                primaryKeys: pks,
+              )
             : null;
         if (cols.isEmpty && outRows.isEmpty) {
           session.statusLine = 'Command completed.';
@@ -509,7 +513,11 @@ class _SqliteSqlWorkspaceState extends material.State<SqliteSqlWorkspace> {
       setState(() {
         session.rows = newRows;
         session.stagingBuffer =
-            DataGridStagingBuffer(columns: session.columns, rows: session.rows);
+            DataGridStagingBuffer(
+          columns: session.columns,
+          rows: session.rows,
+          primaryKeys: session.resultGridPrimaryKeys,
+        );
         session.savingChanges = false;
       });
     } catch (e) {

lib/features/sqlite/sqlite_table_view.dart

@@ -136,6 +136,7 @@ class _SqliteTableViewState extends material.State<SqliteTableView> {
         columns: _columnNames,
         rows: _rows,
         enabled: _editingEnabled,
+        primaryKeys: _primaryKeys,
       );
     }
     if (mounted) setState(() {});
@@ -262,6 +263,7 @@ class _SqliteTableViewState extends material.State<SqliteTableView> {
       columns: columns,
       rows: rows,
       enabled: _editingEnabled,
+      primaryKeys: _primaryKeys,
     );
   }
 
@@ -408,6 +410,7 @@ class _SqliteTableViewState extends material.State<SqliteTableView> {
           columns: _columnNames,
           rows: newRows,
           enabled: _editingEnabled,
+          primaryKeys: _primaryKeys,
         );
         _isSaving = false;
       });

lib/features/workspace/data_grid_staging_buffer.dart

@@ -26,7 +26,9 @@ class DataGridStagingBuffer extends ChangeNotifier {
   DataGridStagingBuffer({
     required List<String> columns,
     required List<List<String>> rows,
+    List<String> primaryKeys = const [],
   })  : _originalColumns = List.unmodifiable(columns),
+        _primaryKeys = List.unmodifiable(primaryKeys),
         _originalRows = List.unmodifiable(
           rows.map((r) => List<String>.unmodifiable(r)).toList(),
         ) {
@@ -36,6 +38,10 @@ class DataGridStagingBuffer extends ChangeNotifier {
   final List<String> _originalColumns;
   final List<List<String>> _originalRows;
 
+  /// Primary key column names; blanked when a row is duplicated so the
+  /// database can generate a fresh key instead of hitting a unique violation.
+  final List<String> _primaryKeys;
+
   /// Map of `rowIndex -> (colIndex -> stagedValue)` for modified cells in baseline rows.
   final Map<int, Map<int, String>> _modifiedCells = {};
 
@@ -322,6 +328,25 @@ class DataGridStagingBuffer extends ChangeNotifier {
     );
   }
 
+  /// Stages a copy of the row at [index] (baseline or already inserted) as a
+  /// new row with its primary key cells blanked.
+  ///
+  /// Composite or natural keys the database cannot generate stay blank for the
+  /// user to fill in before saving. No-op when [index] is out of range.
+  void duplicateRow(int index) {
+    if (index < 0 || index >= totalRowCount) return;
+    final pkNames = _primaryKeys
+        .map((pk) => TableMutationEngine.unquoteIdentifier(pk).toLowerCase())
+        .toSet();
+    final row = List<String>.generate(_originalColumns.length, (c) {
+      final name = TableMutationEngine.unquoteIdentifier(_originalColumns[c])
+          .toLowerCase();
+      if (pkNames.contains(name)) return '';
+      return _sanitizeNull(getCellValue(index, c));
+    });
+    addRow(row);
+  }
+
   /// Returns the full list of effective rows (original with modifications applied + inserted rows).
   ///
   /// Row indices stay aligned with the grid (rows marked for deletion are still

lib/features/workspace/result_grid_view.dart

@@ -1509,8 +1509,7 @@ class _VirtualResultGridState extends material.State<VirtualResultGrid> {
 
   void _handleDuplicateRow(int row) {
     if (widget.stagingBuffer == null || row >= _sortedRows.length) return;
-    final rowData = _sortedRows[row];
-    widget.stagingBuffer!.addRow(List<String>.from(rowData));
+    widget.stagingBuffer!.duplicateRow(_toModelRowIndex(row));
   }
 
   void _handleToggleDeleteRow(int row) {

lib/features/workspace/table_view_staging.dart

@@ -90,10 +90,15 @@ DataGridStagingBuffer? replaceTableViewStagingBuffer({
   required List<String> columns,
   required List<List<String>> rows,
   required bool enabled,
+  List<String> primaryKeys = const [],
 }) {
   previous?.dispose();
   if (!enabled || columns.isEmpty) return null;
-  return DataGridStagingBuffer(columns: columns, rows: rows);
+  return DataGridStagingBuffer(
+    columns: columns,
+    rows: rows,
+    primaryKeys: primaryKeys,
+  );
 }
 
 /// Confirms discarding dirty staged edits. Returns true when it is safe to proceed.

test/features/workspace/data_grid_staging_buffer_test.dart

@@ -153,6 +153,62 @@ void main() {
       ]);
     });
 
+    test('duplicateRow blanks primary key cells and keeps other values', () {
+      final keyed = DataGridStagingBuffer(
+        columns: ['id', 'name', 'email'],
+        rows: [
+          ['42', 'Alice', 'alice@test.com'],
+        ],
+        primaryKeys: ['id'],
+      );
+      addTearDown(keyed.dispose);
+      keyed.setCell(0, 1, 'Alice Edited');
+
+      keyed.duplicateRow(0);
+
+      expect(keyed.insertedRowCount, 1);
+      expect(keyed.effectiveRows.last, ['', 'Alice Edited', 'alice@test.com']);
+      expect(keyed.getRowStatus(1), StagedRowStatus.inserted);
+    });
+
+    test(
+        'duplicateRow blanks every column of a composite key, case-insensitively',
+        () {
+      final keyed = DataGridStagingBuffer(
+        columns: ['Org', 'user_id', 'role'],
+        rows: [
+          ['1', '2', 'admin'],
+        ],
+        primaryKeys: ['org', '"user_id"'],
+      );
+      addTearDown(keyed.dispose);
+
+      keyed.duplicateRow(0);
+
+      expect(keyed.effectiveRows.last, ['', '', 'admin']);
+    });
+
+    test('duplicateRow copies staged NULLs as NULL and can copy inserted rows',
+        () {
+      buffer.setCellNull(0, 2);
+      buffer.duplicateRow(0);
+      expect(buffer.effectiveRows.last, ['1', 'Alice', 'NULL']);
+
+      buffer.duplicateRow(3); // the row inserted above
+      expect(buffer.insertedRowCount, 2);
+    });
+
+    test(
+        'duplicateRow without primary keys copies verbatim; bad index is a no-op',
+        () {
+      buffer.duplicateRow(1);
+      expect(buffer.effectiveRows.last, ['2', 'Bob', 'bob@test.com']);
+
+      buffer.duplicateRow(-1);
+      buffer.duplicateRow(99);
+      expect(buffer.insertedRowCount, 1);
+    });
+
     test('committedRows equals baseline when clean', () {
       expect(buffer.committedRows, buffer.originalRows);
     });