diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6764994..092ea70 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # Changelog
 
+## 3.2.1
+
+- Added or fixed decoders support for `QueryMode.simple`:
+  `double`, `real`, `timestampWithTimezone`, `timestampWithoutTimezone`,
+  `date`, `numeric`, `json`, `jsonb` [#338](https://github.com/isoos/postgresql-dart/pull/338) by [pst9354](https://github.com/pst9354).
+
 ## 3.2.0
 
 - Support for `tsvector` and `tsquery` types.
diff --git a/lib/src/types/text_codec.dart b/lib/src/types/text_codec.dart
index c6911d5..2d38740 100644
--- a/lib/src/types/text_codec.dart
+++ b/lib/src/types/text_codec.dart
@@ -240,7 +240,7 @@ class PostgresTextDecoder {
         return int.parse(di.asText);
       case TypeOid.real:
       case TypeOid.double:
-        return num.parse(di.asText);
+        return double.parse(di.asText);
       case TypeOid.boolean:
         // In text data format when using simple query protocol, "true" & "false"
         // are represented as `t` and `f`,  respectively.
@@ -255,12 +255,31 @@ class PostgresTextDecoder {
 
       case TypeOid.timestampWithTimezone:
       case TypeOid.timestampWithoutTimezone:
-      case TypeOid.interval:
+        final raw = DateTime.parse(di.asText);
+        return DateTime.utc(
+          raw.year,
+          raw.month,
+          raw.day,
+          raw.hour,
+          raw.minute,
+          raw.second,
+          raw.millisecond,
+          raw.microsecond,
+        );
+
       case TypeOid.numeric:
-      case TypeOid.byteArray:
+        return di.asText;
+
       case TypeOid.date:
+        final raw = DateTime.parse(di.asText);
+        return DateTime.utc(raw.year, raw.month, raw.day);
+
       case TypeOid.json:
       case TypeOid.jsonb:
+        return jsonDecode(di.asText);
+
+      case TypeOid.interval:
+      case TypeOid.byteArray:
       case TypeOid.uuid:
       case TypeOid.point:
       case TypeOid.booleanArray:
diff --git a/pubspec.yaml b/pubspec.yaml
index 304bd71..922aab0 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: postgres
 description: PostgreSQL database driver. Supports statement reuse and binary protocol and connection pooling.
-version: 3.2.0
+version: 3.2.1
 homepage: https://github.com/isoos/postgresql-dart
 topics:
   - sql
diff --git a/test/decode_test.dart b/test/decode_test.dart
index 8597523..1bcce74 100644
--- a/test/decode_test.dart
+++ b/test/decode_test.dart
@@ -4,6 +4,69 @@ import 'package:test/test.dart';
 import 'docker.dart';
 
 void main() {
+  withPostgresServer('simple query protocol decode', (server) {
+    late Connection conn;
+    setUp(() async {
+      conn = await server.newConnection(queryMode: QueryMode.simple);
+    });
+    tearDown(() async {
+      await conn.close();
+    });
+
+    test('double', () async {
+      final rs = await conn.execute('SELECT 3.14::DOUBLE PRECISION');
+      expect(rs.single.single, 3.14);
+    });
+
+    test('timestamp with time zones', () async {
+      final rs = await conn.execute(
+          "SELECT '1999-01-08 04:05:06 -8:00'::TIMESTAMP WITH TIME ZONE");
+      final item = rs.single.single as DateTime;
+      expect(item.toIso8601String(), '1999-01-08T12:05:06.000Z');
+    });
+
+    test('timestamp without time zones', () async {
+      final rs = await conn
+          .execute("SELECT '1999-01-08 04:05:06'::TIMESTAMP WITHOUT TIME ZONE");
+      final item = rs.single.single as DateTime;
+      expect(item.toIso8601String(), '1999-01-08T04:05:06.000Z');
+    });
+
+    test('interval', () async {
+      final rs = await conn.execute(
+          "SELECT '2 years 15 months 100 weeks 99 hours 123456789 milliseconds'::INTERVAL");
+      final item = rs.single.single;
+      expect((item as UndecodedBytes).asString,
+          '3 years 3 mons 700 days 133:17:36.789');
+      // should be:
+      // expect(item, Interval(months: 39, days: 700, microseconds: 479856789000));
+    });
+
+    test('numeric', () async {
+      final rs = await conn.execute('SELECT 3.141::NUMERIC(5,2)');
+      final item = rs.single.single;
+      expect(item, '3.14');
+    });
+
+    test('date', () async {
+      final rs = await conn.execute("SELECT '1999-01-08'::DATE");
+      final item = rs.single.single as DateTime;
+      expect(item.toIso8601String(), '1999-01-08T00:00:00.000Z');
+    });
+
+    test('json', () async {
+      final rs = await conn.execute("SELECT '{\"a\": 1}'::JSON");
+      final item = rs.single.single;
+      expect(item, {'a': 1});
+    });
+
+    test('jsonb', () async {
+      final rs = await conn.execute("SELECT '{\"a\": 1}'::JSONB");
+      final item = rs.single.single;
+      expect(item, {'a': 1});
+    });
+  });
+
   withPostgresServer('decode', (server) {
     late Connection connection;
     setUp(() async {
diff --git a/test/docker.dart b/test/docker.dart
index d8b6373..6338fc6 100644
--- a/test/docker.dart
+++ b/test/docker.dart
@@ -62,6 +62,7 @@ class PostgresServer {
   Future<Connection> newConnection({
     ReplicationMode replicationMode = ReplicationMode.none,
     SslMode? sslMode,
+    QueryMode? queryMode,
   }) async {
     return Connection.open(
       await endpoint(),
@@ -71,6 +72,7 @@ class PostgresServer {
         replicationMode: replicationMode,
         transformer: loggingTransformer('conn'),
         sslMode: sslMode,
+        queryMode: queryMode,
       ),
     );
   }