From 0264a8fbe19fff958803afd94d2911b32b76bd83 Mon Sep 17 00:00:00 2001
From: Tree NG <tt88dev@gmail.com>
Date: Wed, 3 Jan 2024 14:06:14 +0800
Subject: [PATCH] Bugfix feature - String columns to support MAX and MIN

---
 .gitignore                                         |  1 +
 .../query_builder/expressions/aggregate.dart       | 14 ++++++++++++++
 .../test/database/expressions/aggregate_test.dart  |  3 +++
 3 files changed, 18 insertions(+)

diff --git a/.gitignore b/.gitignore
index f7932aa5..685e2c62 100644
--- a/.gitignore
+++ b/.gitignore
@@ -20,3 +20,4 @@ docs/**/*.g.dart
 */build/
 drift/extension/devtools/build
 **/pubspec_overrides.yaml
+**.history/
\ No newline at end of file
diff --git a/drift/lib/src/runtime/query_builder/expressions/aggregate.dart b/drift/lib/src/runtime/query_builder/expressions/aggregate.dart
index 2921b3c5..b2f99b52 100644
--- a/drift/lib/src/runtime/query_builder/expressions/aggregate.dart
+++ b/drift/lib/src/runtime/query_builder/expressions/aggregate.dart
@@ -30,6 +30,20 @@ extension BaseAggregate<DT extends Object> on Expression<DT> {
         filter: filter, distinct: distinct);
   }
 
+  /// Return the maximum of all non-null values in this group.
+  ///
+  /// If there are no non-null values in the group, returns null.
+  /// {@macro drift_aggregate_filter}
+  Expression<DT> max({Expression<bool>? filter}) =>
+      _AggregateExpression('MAX', [this], filter: filter);
+
+  /// Return the minimum of all non-null values in this group.
+  ///
+  /// If there are no non-null values in the group, returns null.
+  /// {@macro drift_aggregate_filter}
+  Expression<DT> min({Expression<bool>? filter}) =>
+      _AggregateExpression('MIN', [this], filter: filter);
+
   /// Returns the concatenation of all non-null values in the current group,
   /// joined by the [separator].
   ///
diff --git a/drift/test/database/expressions/aggregate_test.dart b/drift/test/database/expressions/aggregate_test.dart
index 695443a1..7f201f04 100644
--- a/drift/test/database/expressions/aggregate_test.dart
+++ b/drift/test/database/expressions/aggregate_test.dart
@@ -5,6 +5,7 @@ import '../../test_utils/test_utils.dart';
 
 void main() {
   const foo = CustomExpression<int>('foo', precedence: Precedence.primary);
+  const s1 = CustomExpression<String>('s1', precedence: Precedence.primary);
 
   group('count', () {
     test('all', () {
@@ -49,10 +50,12 @@ void main() {
 
   test('max', () {
     expect(foo.max(), generates('MAX(foo)'));
+    expect(s1.max(), generates('MAX(s1)'));
   });
 
   test('min', () {
     expect(foo.min(), generates('MIN(foo)'));
+    expect(s1.min(), generates('MIN(s1)'));
   });
 
   test('sum', () {