diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7199247..e2fdb4d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- **Postgres timestamptz / bytea / jsonb / arrays (#789)** — Table Browser and SQL results encode cells as PG literals (ISO timestamps, `\x` hex for bytea, JSON text for jsonb, `{1,2,3}` for arrays) instead of `Object.toString`. Schema uses `udt_name` so `ARRAY` / `USER-DEFINED` round-trip through `formatLiteral`.
 - **Postgres host/port SSL (#790)** — Host/port Use SSL/TLS stays `sslmode=require` (encrypt, no CA check) unless a Root CA is set, then `verify-full`. A URI `sslmode=` value still wins. The form documents the MITM tradeoff and writes `sslmode=verify-full` when saving a Root CA.
 - **Postgres custom-SQL allowlist (#791)** — Table Browser SQL dialog classifies the first statement after comments instead of substring `contains('insert ')`. `SELECT inserted_at` is allowed; `SELECT 1; DELETE FROM t` is rejected. `WITH … INSERT` is a write; `TABLE` / `VALUES` / `(SELECT …)` stay allowed.
 - **SQLite getObjectDdl bind (#796)** — DDL lookup uses `WHERE name = ?` with a positional list. `:name` plus `[objectName]` did not bind, so the dialog showed **No definition found** for tables that exist.
diff --git a/lib/core/database/postgres_connection.dart b/lib/core/database/postgres_connection.dart
index dffbfb7..e6190e3 100644
--- a/lib/core/database/postgres_connection.dart
+++ b/lib/core/database/postgres_connection.dart
@@ -10,6 +10,7 @@ import 'package:querya_desktop/core/storage/local_db.dart';
 import 'package:postgres/src/connection_string.dart' show parseConnectionString;
 
 import 'postgres_metadata.dart';
+import 'postgres_result_cells.dart';
 import 'table_schema_meta.dart';
 
 /// Replaces the database in a `postgresql://` / `postgres://` URI (path or
@@ -421,7 +422,7 @@ class PostgresConnection {
     }
     final colsRs = await _conn!.execute(
       Sql.named(
-        'SELECT column_name, data_type, is_nullable, column_default, '
+        'SELECT column_name, data_type, udt_name, is_nullable, column_default, '
         'is_generated, is_identity, identity_generation '
         'FROM information_schema.columns '
         'WHERE table_schema = @schema AND table_name = @table '
@@ -450,15 +451,18 @@ class PostgresConnection {
 
     for (final r in colsRs) {
       final name = r[0] as String? ?? '';
-      final dataType = r[1] as String? ?? '';
-      final isNullable = (r[2] as String? ?? 'YES').toUpperCase() == 'YES';
+      final dataType = postgresColumnSchemaType(
+        dataType: r[1] as String? ?? '',
+        udtName: r[2] as String? ?? '',
+      );
+      final isNullable = (r[3] as String? ?? 'YES').toUpperCase() == 'YES';
       final isPk = primaryKeys.contains(name);
       final pkPos = isPk ? primaryKeys.indexOf(name) + 1 : null;
-      final dflt = r[3]?.toString();
+      final dflt = r[4]?.toString();
       final isGenerated =
-          (r[4] as String? ?? 'NEVER').toUpperCase() == 'ALWAYS';
-      final isIdentity = (r[5] as String? ?? 'NO').toUpperCase() == 'YES';
-      final identityGeneration = (r[6] as String? ?? '').toUpperCase();
+          (r[5] as String? ?? 'NEVER').toUpperCase() == 'ALWAYS';
+      final isIdentity = (r[6] as String? ?? 'NO').toUpperCase() == 'YES';
+      final identityGeneration = (r[7] as String? ?? '').toUpperCase();
       final omitOnInsert =
           isGenerated || (isIdentity && identityGeneration == 'ALWAYS');
       final hasServerDefault = (dflt != null && dflt.isNotEmpty) ||
diff --git a/lib/core/database/postgres_result_cells.dart b/lib/core/database/postgres_result_cells.dart
new file mode 100644
index 0000000..307daa4
--- /dev/null
+++ b/lib/core/database/postgres_result_cells.dart
@@ -0,0 +1,154 @@
+import 'dart:convert';
+import 'dart:typed_data';
+
+import 'package:postgres/postgres.dart';
+
+/// Schema type for the grid codec: prefer `udt_name` over `data_type`.
+///
+/// `information_schema.columns.data_type` is `ARRAY` / `USER-DEFINED` for
+/// arrays, enums, and domains — too coarse for `formatLiteral`.
+String postgresColumnSchemaType({
+  required String dataType,
+  required String udtName,
+}) {
+  final dt = dataType.trim();
+  final udt = udtName.trim();
+  final dtLower = dt.toLowerCase();
+  if (dtLower == 'array') {
+    if (udt.startsWith('_') && udt.length > 1) {
+      return '${udt.substring(1)}[]';
+    }
+    return udt.isNotEmpty ? '$udt[]' : dt;
+  }
+  if (dtLower == 'user-defined') {
+    return udt.isNotEmpty ? udt : dt;
+  }
+  if (udt.isNotEmpty) return udt;
+  return dt;
+}
+
+/// PG-literal-friendly cell text: ISO timestamps, `\x` hex for bytea, JSON
+/// for jsonb, `{1,2,3}` for arrays. Null → `NULL`.
+String postgresResultCellToDisplayString(
+  Object? value, {
+  int? typeOid,
+  String? dataTypeName,
+}) {
+  if (value == null) return 'NULL';
+  if (value is UndecodedBytes) return value.asString;
+
+  if (value is Uint8List) {
+    return postgresByteaHexDisplay(value);
+  }
+  if (_isByteaType(typeOid, dataTypeName)) {
+    if (value is List<int>) {
+      return postgresByteaHexDisplay(Uint8List.fromList(value));
+    }
+    return postgresByteaHexDisplayFromCell(value);
+  }
+
+  if (value is DateTime) {
+    if (_isDateOnly(typeOid, dataTypeName)) {
+      return value.toIso8601String().split('T').first;
+    }
+    return value.toIso8601String();
+  }
+
+  if (value is bool) return value ? 'true' : 'false';
+
+  if (_isJsonType(typeOid, dataTypeName) || value is Map) {
+    if (value is String) return value;
+    try {
+      return json.encode(value);
+    } catch (_) {
+      return value.toString();
+    }
+  }
+
+  if (value is List) {
+    return postgresArrayLiteral(value);
+  }
+
+  return value.toString();
+}
+
+/// PostgreSQL bytea text `\xdeadbeef`.
+String postgresByteaHexDisplay(Uint8List bytes) {
+  final out = StringBuffer(r'\x');
+  for (final b in bytes) {
+    out.write(b.toRadixString(16).padLeft(2, '0'));
+  }
+  return out.toString();
+}
+
+String postgresByteaHexDisplayFromCell(Object value) {
+  final raw = value.toString().trim();
+  if (raw == 'NULL' || raw == 'null') return 'NULL';
+  var hex = raw;
+  if (hex.startsWith(r'\x') ||
+      hex.startsWith(r'\X') ||
+      hex.startsWith('0x') ||
+      hex.startsWith('0X')) {
+    hex = hex.substring(2);
+  } else if ((hex.startsWith("x'") || hex.startsWith("X'")) &&
+      hex.endsWith("'")) {
+    hex = hex.substring(2, hex.length - 1);
+  } else {
+    return postgresByteaHexDisplay(
+      Uint8List.fromList(raw.codeUnits.map((u) => u & 0xFF).toList()),
+    );
+  }
+  final clean = hex.replaceAll(RegExp(r'[^0-9a-fA-F]'), '').toLowerCase();
+  return '\\x$clean';
+}
+
+/// PostgreSQL array text `{1,2,3}` / `{Alpha,"a b"}` (not Dart `[…]`).
+String postgresArrayLiteral(List<dynamic> items) {
+  final inner = items.map(_postgresArrayElement).join(',');
+  return '{$inner}';
+}
+
+String _postgresArrayElement(Object? e) {
+  if (e == null) return 'NULL';
+  if (e is Uint8List) return postgresByteaHexDisplay(e);
+  if (e is List) return postgresArrayLiteral(e);
+  if (e is Map) {
+    return _postgresArrayQuote(json.encode(e));
+  }
+  if (e is DateTime) return e.toIso8601String();
+  if (e is bool) return e ? 't' : 'f';
+  if (e is String) return _postgresArrayQuote(e);
+  return e.toString();
+}
+
+String _postgresArrayQuote(String s) {
+  return '"${s.replaceAll(r'\', r'\\').replaceAll('"', r'\"')}"';
+}
+
+bool _isByteaType(int? typeOid, String? dataTypeName) {
+  if (typeOid != null && typeOid == Type.byteArray.oid) return true;
+  final t = dataTypeName?.toLowerCase() ?? '';
+  if (_isPgArrayTypeName(t)) return false;
+  return t.contains('bytea');
+}
+
+bool _isJsonType(int? typeOid, String? dataTypeName) {
+  if (typeOid != null &&
+      (typeOid == Type.json.oid || typeOid == Type.jsonb.oid)) {
+    return true;
+  }
+  final t = dataTypeName?.toLowerCase() ?? '';
+  if (_isPgArrayTypeName(t)) return false;
+  return t.contains('json');
+}
+
+bool _isDateOnly(int? typeOid, String? dataTypeName) {
+  if (typeOid != null && typeOid == Type.date.oid) return true;
+  final t = dataTypeName?.toLowerCase().trim() ?? '';
+  return t == 'date';
+}
+
+bool _isPgArrayTypeName(String lower) {
+  return lower.contains('[]') ||
+      (lower.startsWith('_') && !lower.contains(' '));
+}
diff --git a/lib/core/database/table_mutation_engine.dart b/lib/core/database/table_mutation_engine.dart
index b414ea6..e8790fc 100644
--- a/lib/core/database/table_mutation_engine.dart
+++ b/lib/core/database/table_mutation_engine.dart
@@ -142,6 +142,13 @@ abstract final class TableMutationEngine {
         lower.startsWith('bit');
   }
 
+  static bool _isArrayType(String dataTypeName) {
+    final lower = dataTypeName.toLowerCase().trim();
+    if (lower.contains('[]')) return true;
+    if (lower == 'array') return true;
+    return lower.startsWith('_') && !lower.contains(' ');
+  }
+
   /// Public alias of [_isBoolType] for grid display / validators.
   static bool isBoolType(String dataTypeName) => _isBoolType(dataTypeName);
 
@@ -165,6 +172,13 @@ abstract final class TableMutationEngine {
     final trimmed = value.trim();
 
     if (dataTypeName != null && dataTypeName.isNotEmpty) {
+      if (_isArrayType(dataTypeName)) {
+        if (trimmed == 'NULL' || trimmed == 'null') {
+          return 'NULL';
+        }
+        return _formatStringLiteral(value, dialect);
+      }
+
       if (_isBinaryType(dataTypeName)) {
         if (trimmed == 'NULL' || trimmed == 'null') {
           return 'NULL';
diff --git a/lib/features/postgresql/postgres_result_utils.dart b/lib/features/postgresql/postgres_result_utils.dart
index a6aaf18..da0e494 100644
--- a/lib/features/postgresql/postgres_result_utils.dart
+++ b/lib/features/postgresql/postgres_result_utils.dart
@@ -1,19 +1,32 @@
-/// Serializable row batch for [convertPostgresResultRowsToStrings] in a worker isolate.
+import 'package:querya_desktop/core/database/postgres_result_cells.dart';
+
+/// Serializable row batch for [convertPostgresResultRowsToStrings].
 class PostgresResultConvertJob {
   const PostgresResultConvertJob({
     required this.rowValues,
+    this.columnTypeOids,
+    this.columnDataTypes,
   });
 
   final List<List<Object?>> rowValues;
+  final List<int>? columnTypeOids;
+  final List<String?>? columnDataTypes;
 }
 
-/// Converts PostgreSQL result cell values to display strings off the UI thread.
-List<List<String>> convertPostgresResultRowsToStrings(PostgresResultConvertJob job) {
-  return job.rowValues
-      .map(
-        (row) => row
-            .map((value) => value == null ? 'NULL' : value.toString())
-            .toList(),
-      )
-      .toList();
+/// Converts PostgreSQL result cells to PG-literal-friendly display strings.
+List<List<String>> convertPostgresResultRowsToStrings(
+    PostgresResultConvertJob job) {
+  final oids = job.columnTypeOids;
+  final types = job.columnDataTypes;
+  return [
+    for (final row in job.rowValues)
+      [
+        for (var i = 0; i < row.length; i++)
+          postgresResultCellToDisplayString(
+            row[i],
+            typeOid: oids != null && i < oids.length ? oids[i] : null,
+            dataTypeName: types != null && i < types.length ? types[i] : null,
+          ),
+      ],
+  ];
 }
diff --git a/lib/features/postgresql/postgres_sql_workspace.dart b/lib/features/postgresql/postgres_sql_workspace.dart
index 46f95e6..8574f96 100644
--- a/lib/features/postgresql/postgres_sql_workspace.dart
+++ b/lib/features/postgresql/postgres_sql_workspace.dart
@@ -18,6 +18,7 @@ import 'package:querya_desktop/core/storage/app_settings.dart';
 import 'package:querya_desktop/core/storage/local_db.dart';
 import 'package:querya_desktop/core/ui/querya_shell_status.dart';
 import 'package:querya_desktop/features/postgresql/postgres_object_kind.dart';
+import 'package:querya_desktop/features/postgresql/postgres_result_utils.dart';
 import 'package:querya_desktop/features/postgresql/postgres_table_utils.dart';
 import 'package:querya_desktop/features/settings/preferences_dialog.dart';
 import 'package:querya_desktop/features/settings/sql_statement_timeout_dropdown.dart';
@@ -475,7 +476,15 @@ class _PostgresSqlWorkspaceState extends material.State<PostgresSqlWorkspace> {
         n++;
       }
 
-      final outRows = await convertResultRowsToStringsAdaptive(rawRows);
+      final converted = convertPostgresResultRowsToStrings(
+        PostgresResultConvertJob(
+          rowValues: rawRows,
+          columnTypeOids: [
+            for (final c in schema.columns) c.typeOid,
+          ],
+        ),
+      );
+      final outRows = await convertResultRowsToStringsAdaptive(converted);
 
       final target = SqlTableTargetExtractor.extract(userSql);
       var pks = const <String>[];
diff --git a/lib/features/postgresql/postgres_table_utils.dart b/lib/features/postgresql/postgres_table_utils.dart
index e4bfb33..029c635 100644
--- a/lib/features/postgresql/postgres_table_utils.dart
+++ b/lib/features/postgresql/postgres_table_utils.dart
@@ -1,6 +1,7 @@
 /// Utilities for PostgreSQL table data view (quoting, row conversion).
 library;
 
+import 'package:querya_desktop/core/database/postgres_result_cells.dart';
 import 'package:querya_desktop/core/database/sql_limit.dart';
 
 /// Default page size for table browse and the SQL template filled from the tree.
@@ -24,13 +25,10 @@ String quotePostgresIdentifier(String name) {
 
 /// Converts raw result rows (list of dynamic values per row) to list of string rows.
 List<List<String>> convertResultRowsToStrings(List<List<dynamic>> rawRows) {
-  return rawRows.map((row) {
-    return row.map((value) {
-      if (value == null) return 'NULL';
-      if (value is DateTime) return value.toIso8601String();
-      return value.toString();
-    }).toList();
-  }).toList();
+  return [
+    for (final row in rawRows)
+      [for (final value in row) postgresResultCellToDisplayString(value)],
+  ];
 }
 
 /// Whether [sql] is allowed for the Table Browser custom-SQL dialog.
diff --git a/lib/features/postgresql/postgres_table_view.dart b/lib/features/postgresql/postgres_table_view.dart
index 48fe547..e06fdbb 100644
--- a/lib/features/postgresql/postgres_table_view.dart
+++ b/lib/features/postgresql/postgres_table_view.dart
@@ -2,6 +2,7 @@ import 'dart:async' show unawaited;
 
 import 'package:flutter/material.dart' as material;
 import 'package:flutter/services.dart' show LogicalKeyboardKey;
+import 'package:postgres/postgres.dart';
 import 'package:querya_desktop/core/database/postgres_connection.dart';
 import 'package:querya_desktop/core/database/postgres_service.dart';
 import 'package:querya_desktop/core/database/postgres_sql.dart';
@@ -9,6 +10,7 @@ import 'package:querya_desktop/core/database/result_row_string_convert.dart';
 import 'package:querya_desktop/core/database/table_mutation_engine.dart';
 import 'package:querya_desktop/core/database/table_schema_meta.dart';
 import 'package:querya_desktop/core/storage/local_db.dart';
+import 'package:querya_desktop/features/postgresql/postgres_result_utils.dart';
 import 'package:querya_desktop/features/postgresql/postgres_sql_editor_dialog.dart';
 import 'package:querya_desktop/features/postgresql/postgres_table_privileges_dialog.dart';
 import 'package:querya_desktop/features/postgresql/postgres_table_toolbar.dart';
@@ -251,6 +253,28 @@ class _PostgresTableViewState extends material.State<PostgresTableView> {
     );
   }
 
+  Future<List<List<String>>> _postgresRowsToDisplayStrings(
+    Result result,
+    List<String> colNames,
+  ) async {
+    final rawRows = <List<Object?>>[
+      for (final row in result)
+        List<Object?>.generate(row.length, (i) => row[i]),
+    ];
+    final converted = convertPostgresResultRowsToStrings(
+      PostgresResultConvertJob(
+        rowValues: rawRows,
+        columnTypeOids: [
+          for (final c in result.schema.columns) c.typeOid,
+        ],
+        columnDataTypes: [
+          for (final n in colNames) _columnDataTypes[n],
+        ],
+      ),
+    );
+    return convertResultRowsToStringsAdaptive(converted);
+  }
+
   /// [refreshCount] runs `COUNT(*)` (e.g. first load or Refresh). Pagination only runs SELECT.
   Future<void> _fetch({bool refreshCount = false}) async {
     final conn = _connection;
@@ -296,12 +320,7 @@ class _PostgresTableViewState extends material.State<PostgresTableView> {
         (i) => result.schema.columns[i].columnName ?? 'col_$i',
       );
 
-      final rawRows = <List<Object?>>[
-        for (final row in result)
-          List<Object?>.generate(row.length, (i) => row[i]),
-      ];
-
-      final stringRows = await convertResultRowsToStringsAdaptive(rawRows);
+      final stringRows = await _postgresRowsToDisplayStrings(result, colNames);
 
       if (!mounted) return;
       setState(() {
@@ -351,12 +370,7 @@ class _PostgresTableViewState extends material.State<PostgresTableView> {
         (i) => result.schema.columns[i].columnName ?? 'col_$i',
       );
 
-      final rawRows = <List<Object?>>[
-        for (final row in result)
-          List<Object?>.generate(row.length, (i) => row[i]),
-      ];
-
-      final stringRows = await convertResultRowsToStringsAdaptive(rawRows);
+      final stringRows = await _postgresRowsToDisplayStrings(result, colNames);
 
       if (!mounted) return;
       setState(() {
diff --git a/lib/features/workspace/grid_data_type_validator.dart b/lib/features/workspace/grid_data_type_validator.dart
index 4eb2f69..0b1c117 100644
--- a/lib/features/workspace/grid_data_type_validator.dart
+++ b/lib/features/workspace/grid_data_type_validator.dart
@@ -24,6 +24,11 @@ abstract final class GridDataTypeValidator {
 
     final type = dataTypeName.toLowerCase().trim();
 
+    // PostgreSQL arrays (`integer[]`, `_int4`) are not scalar ints/json.
+    if (type.contains('[]') || (type.startsWith('_') && !type.contains(' '))) {
+      return null;
+    }
+
     // Boolean types (MySQL BOOLEAN is TINYINT(1) — check before generic int)
     if (type == 'bool' || type == 'boolean' || type.startsWith('tinyint(1)')) {
       final lower = value.toLowerCase().trim();
diff --git a/test/core/database/postgres_grid_types_test.dart b/test/core/database/postgres_grid_types_test.dart
new file mode 100644
index 0000000..eeca3dd
--- /dev/null
+++ b/test/core/database/postgres_grid_types_test.dart
@@ -0,0 +1,186 @@
+import 'dart:convert';
+import 'dart:typed_data';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:postgres/postgres.dart';
+import 'package:querya_desktop/core/database/postgres_result_cells.dart';
+import 'package:querya_desktop/core/database/table_mutation_engine.dart';
+import 'package:querya_desktop/features/postgresql/postgres_result_utils.dart';
+import 'package:querya_desktop/features/workspace/grid_data_type_validator.dart';
+
+void main() {
+  group('postgresColumnSchemaType', () {
+    test('ARRAY uses udt_name element plus []', () {
+      expect(
+        postgresColumnSchemaType(dataType: 'ARRAY', udtName: '_int4'),
+        'int4[]',
+      );
+      expect(
+        postgresColumnSchemaType(dataType: 'ARRAY', udtName: '_jsonb'),
+        'jsonb[]',
+      );
+    });
+
+    test('USER-DEFINED uses udt_name (enum / domain)', () {
+      expect(
+        postgresColumnSchemaType(
+          dataType: 'USER-DEFINED',
+          udtName: 'user_role_enum',
+        ),
+        'user_role_enum',
+      );
+    });
+
+    test('prefers udt_name over data_type', () {
+      expect(
+        postgresColumnSchemaType(
+          dataType: 'timestamp with time zone',
+          udtName: 'timestamptz',
+        ),
+        'timestamptz',
+      );
+      expect(
+        postgresColumnSchemaType(dataType: 'bytea', udtName: 'bytea'),
+        'bytea',
+      );
+      expect(
+        postgresColumnSchemaType(dataType: 'jsonb', udtName: 'jsonb'),
+        'jsonb',
+      );
+    });
+  });
+
+  group('all_types display + persist', () {
+    test('timestamptz DateTime displays ISO and persists quoted', () {
+      final dt = DateTime.utc(2026, 8, 26, 10, 30);
+      expect(
+        postgresResultCellToDisplayString(
+          dt,
+          typeOid: Type.timestampTz.oid,
+          dataTypeName: 'timestamptz',
+        ),
+        dt.toIso8601String(),
+      );
+      expect(
+        TableMutationEngine.formatLiteral(
+          dt.toIso8601String(),
+          SqlDialect.postgres,
+          dataTypeName: 'timestamptz',
+        ),
+        "'${dt.toIso8601String()}'",
+      );
+    });
+
+    test('bytea displays \\x hex and persists as bytea literal', () {
+      expect(
+        postgresResultCellToDisplayString(
+          Uint8List.fromList(const [0xde, 0xad, 0xbe, 0xef]),
+          dataTypeName: 'bytea',
+        ),
+        r'\xdeadbeef',
+      );
+      expect(
+        TableMutationEngine.formatLiteral(
+          r'\xdeadbeef',
+          SqlDialect.postgres,
+          dataTypeName: 'bytea',
+        ),
+        r"'\xdeadbeef'::bytea",
+      );
+    });
+
+    test('jsonb Map displays JSON text and persists quoted', () {
+      const decoded = {
+        'id': 42,
+        'user': {'email': 'alice@querya.dev'},
+      };
+      final shown = postgresResultCellToDisplayString(
+        decoded,
+        typeOid: Type.jsonb.oid,
+        dataTypeName: 'jsonb',
+      );
+      expect(json.decode(shown), decoded);
+      expect(
+        TableMutationEngine.formatLiteral(
+          shown,
+          SqlDialect.postgres,
+          dataTypeName: 'jsonb',
+        ),
+        "'$shown'",
+      );
+    });
+
+    test('enum stays a quoted label', () {
+      expect(
+        postgresResultCellToDisplayString(
+          'admin',
+          dataTypeName: 'user_role_enum',
+        ),
+        'admin',
+      );
+      expect(
+        TableMutationEngine.formatLiteral(
+          'admin',
+          SqlDialect.postgres,
+          dataTypeName: 'user_role_enum',
+        ),
+        "'admin'",
+      );
+    });
+
+    test('int[] displays PG array text and persists quoted', () {
+      expect(
+        postgresResultCellToDisplayString(
+          [1, 2, 3, 42, 999],
+          dataTypeName: 'int4[]',
+        ),
+        '{1,2,3,42,999}',
+      );
+      expect(
+        TableMutationEngine.formatLiteral(
+          '{1,2,3,42,999}',
+          SqlDialect.postgres,
+          dataTypeName: 'int4[]',
+        ),
+        "'{1,2,3,42,999}'",
+      );
+      expect(
+        GridDataTypeValidator.validate('{1,2,3}', dataTypeName: 'int4[]'),
+        isNull,
+      );
+    });
+  });
+
+  group('convertPostgresResultRowsToStrings', () {
+    test('maps timestamptz, bytea, jsonb, array — not Object.toString', () {
+      final dt = DateTime.utc(2026, 1, 1, 0, 0, 0);
+      final out = convertPostgresResultRowsToStrings(
+        PostgresResultConvertJob(
+          rowValues: [
+            [
+              dt,
+              Uint8List.fromList(const [0xca, 0xfe]),
+              {'a': true},
+              [10, 20],
+              null,
+            ],
+          ],
+          columnDataTypes: const [
+            'timestamptz',
+            'bytea',
+            'jsonb',
+            'int4[]',
+            'text',
+          ],
+        ),
+      );
+      expect(out.single, [
+        dt.toIso8601String(),
+        r'\xcafe',
+        '{"a":true}',
+        '{10,20}',
+        'NULL',
+      ]);
+    });
+  });
+}
diff --git a/test/features/workspace/grid_data_type_validator_test.dart b/test/features/workspace/grid_data_type_validator_test.dart
index 303e67b..0300415 100644
--- a/test/features/workspace/grid_data_type_validator_test.dart
+++ b/test/features/workspace/grid_data_type_validator_test.dart
@@ -93,6 +93,17 @@ void main() {
       expect(GridDataTypeValidator.validate('123', dataTypeName: 'bytea'), isNotNull); // odd length hex
     });
 
+    test('skips scalar checks for PostgreSQL array types', () {
+      expect(
+        GridDataTypeValidator.validate('{1,2,3}', dataTypeName: 'integer[]'),
+        isNull,
+      );
+      expect(
+        GridDataTypeValidator.validate('{1,2,3}', dataTypeName: '_int4'),
+        isNull,
+      );
+    });
+
     test('allows empty and NULL values regardless of type', () {
       expect(GridDataTypeValidator.validate('', dataTypeName: 'int'), isNull);
       expect(GridDataTypeValidator.validate('NULL', dataTypeName: 'uuid'), isNull);