Allow caching prepared statements

packages/sqlite_async/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.14.4
+
+- Add `SqliteOptions.preparedStatementCacheSize` to cache prepared statements.
+
 ## 0.14.3
 
 - Include identifier of mutexes when a navigator lock attempt is aborted.

packages/sqlite_async/lib/src/native/database/native_sqlite_database.dart

@@ -270,7 +270,8 @@ final class NativeSqliteDatabaseImpl extends SqliteDatabaseImpl {
           [
             for (var i = 0; i < maxReaders; i++) openConnection(isWriter: false)
           ],
-          // TODO: Option to enable prepared statement cache.
+          preparedStatementCacheSize:
+              openFactory.sqliteOptions.preparedStatementCacheSize,
         );
       },
     );

packages/sqlite_async/lib/src/sqlite_options.dart

@@ -43,6 +43,16 @@ final class SqliteOptions {
   /// additional readers on the web.
   final int maxReaders;
 
+  /// The amount of prepared statements to cache.
+  ///
+  /// For each SQLite connection, up to [preparedStatementCacheSize] statements
+  /// will be cached in an LRU cache. This allows re-using prepared statements
+  /// instead of parsing and optimizing them again, which improve performance
+  /// for frequently-used statements like watched queries.
+  ///
+  /// Defaults to 16. To disable caching prepared statements, set this to 0.
+  final int preparedStatementCacheSize;
+
   @Deprecated('Use default SqliteOptions constructor instead')
   const factory SqliteOptions.defaults() = SqliteOptions;
 
@@ -54,6 +64,7 @@ final class SqliteOptions {
     this.lockTimeout = const Duration(seconds: 30),
     this.profileQueries = _profileQueriesByDefault,
     this.maxReaders = defaultMaxReaders,
+    this.preparedStatementCacheSize = 16,
   });
 
   /// Creates a new options instance by applying overrides from parameters.
@@ -64,6 +75,7 @@ final class SqliteOptions {
     WebSqliteOptions? webSqliteOptions,
     bool? profileQueries,
     int? maxReaders,
+    int? preparedStatementCacheSize,
   }) {
     return SqliteOptions(
       journalMode: journalMode,
@@ -73,6 +85,8 @@ final class SqliteOptions {
       lockTimeout: lockTimeout,
       profileQueries: profileQueries ?? this.profileQueries,
       maxReaders: maxReaders ?? this.maxReaders,
+      preparedStatementCacheSize:
+          preparedStatementCacheSize ?? this.preparedStatementCacheSize,
     );
   }
 

packages/sqlite_async/lib/src/web/web_sqlite_open_factory.dart

@@ -64,7 +64,8 @@ base class WebSqliteOpenFactory extends InternalOpenFactory {
   /// can customize the behavior where needed.
   Future<ConnectToRecommendedResult> connectToWorker(
       WebSqlite sqlite, String name) {
-    return sqlite.connectToRecommended(name);
+    return sqlite.connectToRecommended(name,
+        preparedStatementCacheSize: sqliteOptions.preparedStatementCacheSize);
   }
 
   /// Currently this only uses the SQLite Web WASM implementation.

packages/sqlite_async/pubspec.yaml

@@ -14,8 +14,8 @@ topics:
 
 dependencies:
   sqlite3: ^3.2.0
-  sqlite3_web: '>=0.8.0 <0.10.0'
-  sqlite3_connection_pool: ^0.2.4
+  sqlite3_web: ^0.9.2
+  sqlite3_connection_pool: ^0.2.7
   async: ^2.10.0
   collection: ^1.17.0
   meta: ^1.10.0