Use native postgres boolean type instead of integers

drift/lib/src/runtime/query_builder/expressions/variables.dart

@@ -60,7 +60,7 @@ class Variable<T extends Object> extends Expression<T> {
   /// database engine. For instance, a [DateTime] will me mapped to its unix
   /// timestamp.
   dynamic mapToSimpleValue(GenerationContext context) {
-    return context.options.types.mapToSqlVariable(value);
+    return context.options.types.mapToSqlVariable(value, context.dialect);
   }
 
   @override
@@ -83,7 +83,10 @@ class Variable<T extends Object> extends Expression<T> {
       context.buffer
         ..write(mark)
         ..write(explicitStart + context.amountOfVariables);
-      context.introduceVariable(this, mapToSimpleValue(context));
+      context.introduceVariable(
+        this,
+        mapToSimpleValue(context),
+      );
     } else {
       context.buffer.write(mark);
       context.introduceVariable(this, mapToSimpleValue(context));
@@ -117,7 +120,10 @@ class Constant<T extends Object> extends Expression<T> {
 
   @override
   void writeInto(GenerationContext context) {
-    context.buffer.write(context.options.types.mapToSqlLiteral(value));
+    context.buffer.write(context.options.types.mapToSqlLiteral(
+      value,
+      context.dialect,
+    ));
   }
 
   @override

drift/lib/src/runtime/query_builder/schema/column_impl.dart

@@ -16,7 +16,7 @@ class GeneratedColumn<T extends Object> extends Column<T> {
   final bool $nullable;
 
   /// Default constraints generated by drift.
-  final String? _defaultConstraints;
+  final void Function(GenerationContext)? _defaultConstraints;
 
   /// Custom constraints that have been specified for this column.
   ///
@@ -65,8 +65,7 @@ class GeneratedColumn<T extends Object> extends Column<T> {
 
   /// Whether this column has an `AUTOINCREMENT` primary key constraint that was
   /// created by drift.
-  bool get hasAutoIncrement =>
-      _defaultConstraints?.contains('AUTOINCREMENT') == true;
+  final bool hasAutoIncrement;
 
   @override
   String get name => $name;
@@ -78,13 +77,14 @@ class GeneratedColumn<T extends Object> extends Column<T> {
     this.$nullable, {
     this.clientDefault,
     required this.type,
-    String? defaultConstraints,
+    void Function(GenerationContext)? defaultConstraints,
     this.$customConstraints,
     this.defaultValue,
     this.additionalChecks,
     this.requiredDuringInsert = false,
     this.generatedAs,
     this.check,
+    this.hasAutoIncrement = false,
   }) : _defaultConstraints = defaultConstraints;
 
   /// Applies a type converter to this column.
@@ -106,6 +106,7 @@ class GeneratedColumn<T extends Object> extends Column<T> {
       requiredDuringInsert,
       generatedAs,
       check,
+      hasAutoIncrement,
     );
   }
 
@@ -157,9 +158,7 @@ class GeneratedColumn<T extends Object> extends Column<T> {
 
       // these custom constraints refer to builtin constraints from drift
       if (!isSerial && _defaultConstraints != null) {
-        into.buffer
-          ..write(' ')
-          ..write(_defaultConstraints);
+        _defaultConstraints!(into);
       }
     } else if ($customConstraints?.isNotEmpty == true) {
       into.buffer
@@ -265,13 +264,14 @@ class GeneratedColumnWithTypeConverter<D, S extends Object>
     bool nullable,
     S? Function()? clientDefault,
     DriftSqlType<S> type,
-    String? defaultConstraints,
+    void Function(GenerationContext)? defaultConstraints,
     String? customConstraints,
     Expression<S>? defaultValue,
     VerificationResult Function(S?, VerificationMeta)? additionalChecks,
     bool requiredDuringInsert,
     GeneratedAs? generatedAs,
     Expression<bool> Function()? check,
+    bool hasAutoIncrement,
   ) : super(
           name,
           tableName,
@@ -285,6 +285,7 @@ class GeneratedColumnWithTypeConverter<D, S extends Object>
           requiredDuringInsert: requiredDuringInsert,
           generatedAs: generatedAs,
           check: check,
+          hasAutoIncrement: hasAutoIncrement,
         );
 
   /// Compares this column against the mapped [dartValue].

drift/lib/src/runtime/query_builder/statements/select/custom_select.dart

@@ -81,7 +81,11 @@ class QueryRow {
   /// support non-nullable types.
   T read<T>(String key) {
     final type = DriftSqlType.forNullableType<T>();
-    return _db.options.types.read(type, data[key]) as T;
+    return _db.options.types.read(
+      type,
+      data[key],
+      _db.executor.dialect,
+    ) as T;
   }
 
   /// Reads a nullable value from this row.
@@ -90,7 +94,11 @@ class QueryRow {
   /// drift (e.g. booleans, strings, numbers, dates, `Uint8List`s).
   T? readNullable<T extends Object>(String key) {
     final type = DriftSqlType.forType<T>();
-    return _db.options.types.read(type, data[key]);
+    return _db.options.types.read(
+      type,
+      data[key],
+      _db.executor.dialect,
+    );
   }
 
   /// Reads a bool from the column named [key].

drift/lib/src/runtime/query_builder/statements/select/select_with_join.dart

@@ -253,7 +253,11 @@ class JoinedSelectStatement<FirstT extends HasResultSet, FirstD>
         final expr = aliasedColumn.key;
         final value = row[aliasedColumn.value];
 
-        readColumns[expr] = ctx.options.types.read(expr.driftSqlType, value);
+        readColumns[expr] = ctx.options.types.read(
+          expr.driftSqlType,
+          value,
+          ctx.dialect,
+        );
       }
 
       return TypedResult(readTables, QueryRow(row, database), readColumns);

drift/lib/src/runtime/types/mapping.dart

@@ -34,7 +34,10 @@ class SqlTypes {
 
   /// Maps a Dart object to a (possibly simpler) object that can be used as a
   /// parameter in raw sql queries.
-  Object? mapToSqlVariable(Object? dartValue) {
+  Object? mapToSqlVariable(
+    Object? dartValue, [
+    SqlDialect dialect = SqlDialect.sqlite,
+  ]) {
     if (dartValue == null) return null;
 
     // These need special handling, all other types are a direct mapping
@@ -71,7 +74,7 @@ class SqlTypes {
       }
     }
 
-    if (dartValue is bool) {
+    if (dartValue is bool && dialect == SqlDialect.sqlite) {
       return dartValue ? 1 : 0;
     }
 
@@ -80,12 +83,19 @@ class SqlTypes {
 
   /// Maps the [dart] value into a SQL literal that can be embedded in SQL
   /// queries.
-  String mapToSqlLiteral(Object? dart) {
+  String mapToSqlLiteral(
+    Object? dart, [
+    SqlDialect dialect = SqlDialect.sqlite,
+  ]) {
     if (dart == null) return 'NULL';
 
     // todo: Inline and remove types in the next major drift version
     if (dart is bool) {
-      return dart ? '1' : '0';
+      if (dialect == SqlDialect.sqlite) {
+        return dart ? '1' : '0';
+      } else {
+        return dart ? 'true' : 'false';
+      }
     } else if (dart is String) {
       // From the sqlite docs: (https://www.sqlite.org/lang_expr.html)
       // A string constant is formed by enclosing the string in single quotes
@@ -99,7 +109,7 @@ class SqlTypes {
       return dart.toString();
     } else if (dart is DateTime) {
       if (storeDateTimesAsText) {
-        final encoded = mapToSqlVariable(dart).toString();
+        final encoded = mapToSqlVariable(dart, dialect).toString();
         return "'$encoded'";
       } else {
         return (dart.millisecondsSinceEpoch ~/ 1000).toString();
@@ -115,13 +125,21 @@ class SqlTypes {
   }
 
   /// Maps a raw [sqlValue] to Dart given its sql [type].
-  T? read<T extends Object>(DriftSqlType<T> type, Object? sqlValue) {
+  T? read<T extends Object>(
+    DriftSqlType<T> type,
+    Object? sqlValue, [
+    SqlDialect dialect = SqlDialect.sqlite,
+  ]) {
     if (sqlValue == null) return null;
 
     // ignore: unnecessary_cast
     switch (type as DriftSqlType<Object>) {
       case DriftSqlType.bool:
-        return (sqlValue != 0) as T;
+        if (dialect == SqlDialect.sqlite) {
+          return (sqlValue != 0) as T;
+        } else {
+          return sqlValue as T;
+        }
       case DriftSqlType.string:
         return sqlValue.toString() as T;
       case DriftSqlType.bigInt:
@@ -233,7 +251,7 @@ enum DriftSqlType<T extends Object> implements _InternalDriftSqlType<T> {
     // ignore: unnecessary_cast
     switch (this as DriftSqlType<Object>) {
       case DriftSqlType.bool:
-        return dialect == SqlDialect.sqlite ? 'INTEGER' : 'integer';
+        return dialect == SqlDialect.sqlite ? 'INTEGER' : 'boolean';
       case DriftSqlType.string:
         return dialect == SqlDialect.sqlite ? 'TEXT' : 'text';
       case DriftSqlType.bigInt:

drift/test/database/types/bool_test.dart

@@ -0,0 +1,40 @@
+import 'package:drift/drift.dart';
+import 'package:test/test.dart';
+
+void main() {
+  final typeSystem = DriftDatabaseOptions().types;
+
+  group('bool type', () {
+    test('Can read booleans from sqlite', () {
+      expect(typeSystem.read(DriftSqlType.bool, 1, SqlDialect.sqlite), true);
+      expect(typeSystem.read(DriftSqlType.bool, 0, SqlDialect.sqlite), false);
+    });
+
+    test('Can read booleans from postgres', () {
+      expect(
+          typeSystem.read(DriftSqlType.bool, true, SqlDialect.postgres), true);
+      expect(typeSystem.read(DriftSqlType.bool, false, SqlDialect.postgres),
+          false);
+    });
+
+    test('Can be mapped to sqlite constant', () {
+      expect(typeSystem.mapToSqlLiteral(true, SqlDialect.sqlite), '1');
+      expect(typeSystem.mapToSqlLiteral(false, SqlDialect.sqlite), '0');
+    });
+
+    test('Can be mapped to postgres constant', () {
+      expect(typeSystem.mapToSqlLiteral(true, SqlDialect.postgres), 'true');
+      expect(typeSystem.mapToSqlLiteral(false, SqlDialect.postgres), 'false');
+    });
+
+    test('Can be mapped to sqlite variable', () {
+      expect(typeSystem.mapToSqlVariable(true, SqlDialect.sqlite), 1);
+      expect(typeSystem.mapToSqlVariable(false, SqlDialect.sqlite), 0);
+    });
+
+    test('Can be mapped to postgres variable', () {
+      expect(typeSystem.mapToSqlVariable(true, SqlDialect.postgres), true);
+      expect(typeSystem.mapToSqlVariable(false, SqlDialect.postgres), false);
+    });
+  });
+}