diff --git a/lib/core/database/table_mutation_engine.dart b/lib/core/database/table_mutation_engine.dart
index e8790fc..edda4db 100644
--- a/lib/core/database/table_mutation_engine.dart
+++ b/lib/core/database/table_mutation_engine.dart
@@ -304,8 +304,8 @@ abstract final class TableMutationEngine {
         final stagedVal = mod.value;
         if (colIndex < columns.length) {
           final colName = columns[colIndex];
-          final quotedCol = quoteIdentifier(colName, dialect);
-          final colType = columnDataTypes?[colName];
+          final quotedCol = quoteIdentifier(unquoteIdentifier(colName), dialect);
+          final colType = _lookupDataType(columnDataTypes, colName);
           final literal = formatLiteral(stagedVal, dialect, dataTypeName: colType);
           setClauses.add('$quotedCol = $literal');
         }
@@ -339,7 +339,7 @@ abstract final class TableMutationEngine {
 
       for (var c = 0; c < columns.length; c++) {
         final colName = columns[c];
-        final meta = columnMeta?[colName];
+        final meta = _lookupColumnMeta(columnMeta, colName);
         if (meta?.omitOnInsert == true) continue;
 
         final cellVal = c < row.length ? row[c] : (meta == null ? 'NULL' : '');
@@ -349,8 +349,8 @@ abstract final class TableMutationEngine {
           continue;
         }
 
-        final quotedCol = quoteIdentifier(colName, dialect);
-        final colType = columnDataTypes?[colName] ?? meta?.dataType;
+        final quotedCol = quoteIdentifier(unquoteIdentifier(colName), dialect);
+        final colType = _lookupDataType(columnDataTypes, colName) ?? meta?.dataType;
         colNames.add(quotedCol);
         values.add(formatLiteral(cellVal, dialect, dataTypeName: colType));
       }
@@ -401,10 +401,69 @@ abstract final class TableMutationEngine {
       tableName: tableName,
       schema: schema,
       statements: statements,
-      hasPrimaryKey: primaryKeys.isNotEmpty,
+      hasPrimaryKey: _hasMatchingPrimaryKey(columns: columns, primaryKeys: primaryKeys),
     );
   }
 
+  /// Strips enclosing quotes (`"`, ``` ` ```, or `[]`) from an identifier if present.
+  static String unquoteIdentifier(String identifier) {
+    var s = identifier.trim();
+    if ((s.startsWith('"') && s.endsWith('"') && s.length >= 2) ||
+        (s.startsWith('`') && s.endsWith('`') && s.length >= 2) ||
+        (s.startsWith('[') && s.endsWith(']') && s.length >= 2)) {
+      s = s.substring(1, s.length - 1);
+    }
+    return s;
+  }
+
+  /// Normalizes an identifier by stripping enclosing quotes and lowercasing.
+  static String normalizeIdentifier(String identifier) {
+    return unquoteIdentifier(identifier).toLowerCase();
+  }
+
+  static String? _lookupDataType(Map<String, String>? columnDataTypes, String colName) {
+    if (columnDataTypes == null || columnDataTypes.isEmpty) return null;
+    if (columnDataTypes.containsKey(colName)) return columnDataTypes[colName];
+    final unquoted = unquoteIdentifier(colName);
+    if (columnDataTypes.containsKey(unquoted)) return columnDataTypes[unquoted];
+    final norm = normalizeIdentifier(colName);
+    for (final entry in columnDataTypes.entries) {
+      if (normalizeIdentifier(entry.key) == norm) {
+        return entry.value;
+      }
+    }
+    return null;
+  }
+
+  static TableColumnMeta? _lookupColumnMeta(
+    Map<String, TableColumnMeta>? columnMeta,
+    String colName,
+  ) {
+    if (columnMeta == null || columnMeta.isEmpty) return null;
+    if (columnMeta.containsKey(colName)) return columnMeta[colName];
+    final unquoted = unquoteIdentifier(colName);
+    if (columnMeta.containsKey(unquoted)) return columnMeta[unquoted];
+    final norm = normalizeIdentifier(colName);
+    for (final entry in columnMeta.entries) {
+      if (normalizeIdentifier(entry.key) == norm) {
+        return entry.value;
+      }
+    }
+    return null;
+  }
+
+  static bool _hasMatchingPrimaryKey({
+    required List<String> columns,
+    required List<String> primaryKeys,
+  }) {
+    if (primaryKeys.isEmpty) return false;
+    return primaryKeys.any((pk) {
+      if (columns.contains(pk)) return true;
+      final normPk = normalizeIdentifier(pk);
+      return columns.any((c) => normalizeIdentifier(c) == normPk);
+    });
+  }
+
   static String _buildWhereClause({
     required List<String> columns,
     required List<String> primaryKeys,
@@ -416,14 +475,20 @@ abstract final class TableMutationEngine {
 
     if (primaryKeys.isNotEmpty) {
       for (final pk in primaryKeys) {
-        final colIdx = columns.indexOf(pk);
+        var colIdx = columns.indexOf(pk);
+        if (colIdx == -1) {
+          final normPk = normalizeIdentifier(pk);
+          colIdx = columns.indexWhere((c) => normalizeIdentifier(c) == normPk);
+        }
         if (colIdx != -1 && colIdx < row.length) {
-          final colName = quoteIdentifier(pk, dialect);
+          final matchedCol = columns[colIdx];
+          final colName = quoteIdentifier(unquoteIdentifier(matchedCol), dialect);
           final val = row[colIdx];
           if (val == 'NULL' || val == 'null') {
             clauses.add('$colName IS NULL');
           } else {
-            final colType = columnDataTypes?[pk];
+            final colType = _lookupDataType(columnDataTypes, matchedCol) ??
+                _lookupDataType(columnDataTypes, pk);
             clauses.add('$colName = ${formatLiteral(val, dialect, dataTypeName: colType)}');
           }
         }
@@ -434,12 +499,12 @@ abstract final class TableMutationEngine {
     if (clauses.isEmpty) {
       for (var c = 0; c < columns.length; c++) {
         final colName = columns[c];
-        final quotedCol = quoteIdentifier(colName, dialect);
+        final quotedCol = quoteIdentifier(unquoteIdentifier(colName), dialect);
         final val = c < row.length ? row[c] : 'NULL';
         if (val == 'NULL' || val == 'null') {
           clauses.add('$quotedCol IS NULL');
         } else {
-          final colType = columnDataTypes?[colName];
+          final colType = _lookupDataType(columnDataTypes, colName);
           clauses.add('$quotedCol = ${formatLiteral(val, dialect, dataTypeName: colType)}');
         }
       }
diff --git a/test/core/database/table_mutation_engine_test.dart b/test/core/database/table_mutation_engine_test.dart
index 1779d14..ef9efbc 100644
--- a/test/core/database/table_mutation_engine_test.dart
+++ b/test/core/database/table_mutation_engine_test.dart
@@ -537,5 +537,67 @@ void main() {
       );
       expect(mysql.statements.first.sql, 'INSERT INTO `t` () VALUES ()');
     });
+
+    test('resolves primary key with case-insensitive casing (e.g. ID vs id)', () {
+      final plan = TableMutationEngine.generatePlan(
+        dialect: SqlDialect.postgres,
+        tableName: 'users',
+        columns: ['id', 'username', 'email'],
+        primaryKeys: ['ID'],
+        originalRows: [
+          ['42', 'alice', 'alice@example.com'],
+        ],
+        modifiedCells: {
+          0: {1: 'alice_new'},
+        },
+        insertedRows: const [],
+        deletedRowIndices: const {},
+      );
+
+      expect(plan.hasPrimaryKey, isTrue);
+      expect(plan.statementCount, 1);
+      final stmt = plan.statements.first;
+      expect(stmt.type, MutationType.update);
+      // Must generate WHERE "id" = 42, NOT match all columns
+      expect(
+        stmt.sql,
+        'UPDATE "users" SET "username" = \'alice_new\' WHERE "id" = 42',
+      );
+    });
+
+    test('resolves primary key and column names when enclosed in quotes or with different casing', () {
+      final plan = TableMutationEngine.generatePlan(
+        dialect: SqlDialect.postgres,
+        tableName: 'accounts',
+        columns: ['"ACCOUNT_ID"', 'status'],
+        primaryKeys: ['account_id'],
+        originalRows: [
+          ['100', 'active'],
+        ],
+        modifiedCells: const {},
+        insertedRows: const [],
+        deletedRowIndices: {0},
+      );
+
+      expect(plan.hasPrimaryKey, isTrue);
+      expect(plan.statementCount, 1);
+      final stmt = plan.statements.first;
+      expect(stmt.type, MutationType.delete);
+      expect(
+        stmt.sql,
+        'DELETE FROM "accounts" WHERE "ACCOUNT_ID" = 100',
+      );
+    });
+
+    test('unquotes and normalizes identifiers helper methods', () {
+      expect(TableMutationEngine.unquoteIdentifier('"my_col"'), 'my_col');
+      expect(TableMutationEngine.unquoteIdentifier('`my_col`'), 'my_col');
+      expect(TableMutationEngine.unquoteIdentifier('[my_col]'), 'my_col');
+      expect(TableMutationEngine.unquoteIdentifier('my_col'), 'my_col');
+
+      expect(TableMutationEngine.normalizeIdentifier('"USER_ID"'), 'user_id');
+      expect(TableMutationEngine.normalizeIdentifier('`USER_ID`'), 'user_id');
+      expect(TableMutationEngine.normalizeIdentifier('user_id'), 'user_id');
+    });
   });
 }