destroy internally-created prepared statements

Author: jraymakers

api/src/DuckDBConnection.ts

@@ -46,9 +46,13 @@ export class DuckDBConnection {
     types?: DuckDBType[] | Record<string, DuckDBType | undefined>
   ): Promise<DuckDBMaterializedResult> {
     if (values) {
-      const prepared = await this.prepare(sql);
-      prepared.bind(values, types);
-      return prepared.run();
+      const prepared = await this.createPrepared(sql);
+      try {
+        prepared.bind(values, types);
+        return prepared.run();
+      } finally {
+        prepared.destroySync();
+      }
     } else {
       return new DuckDBMaterializedResult(
         await duckdb.query(this.connection, sql)
@@ -86,11 +90,15 @@ export class DuckDBConnection {
     values?: DuckDBValue[] | Record<string, DuckDBValue>,
     types?: DuckDBType[] | Record<string, DuckDBType | undefined>
   ): Promise<DuckDBResult> {
-    const prepared = await this.prepare(sql);
-    if (values) {
-      prepared.bind(values, types);
+    const prepared = await this.createPrepared(sql);
+    try {
+      if (values) {
+        prepared.bind(values, types);
+      }
+      return prepared.stream();
+    } finally {
+      prepared.destroySync();
     }
-    return prepared.stream();
   }
   public async streamAndRead(
     sql: string,
@@ -127,30 +135,41 @@ export class DuckDBConnection {
     values?: DuckDBValue[] | Record<string, DuckDBValue>,
     types?: DuckDBType[] | Record<string, DuckDBType | undefined>
   ): Promise<DuckDBPendingResult> {
-    const prepared = await this.prepare(sql);
-    if (values) {
-      prepared.bind(values, types);
+    const prepared = await this.createPrepared(sql);
+    try {
+      if (values) {
+        prepared.bind(values, types);
+      }
+      return prepared.start();
+    } finally {
+      prepared.destroySync();
     }
-    return prepared.start();
   }
   public async startStream(
     sql: string,
     values?: DuckDBValue[] | Record<string, DuckDBValue>,
     types?: DuckDBType[] | Record<string, DuckDBType | undefined>
   ): Promise<DuckDBPendingResult> {
-    const prepared = await this.prepare(sql);
-    if (values) {
-      prepared.bind(values, types);
+    const prepared = await this.createPrepared(sql);
+    try {
+      if (values) {
+        prepared.bind(values, types);
+      }
+      return prepared.startStream();
+    } finally {
+      prepared.destroySync();
     }
-    return prepared.startStream();
   }
   public async prepare(sql: string): Promise<DuckDBPreparedStatement> {
-    const prepared = new DuckDBPreparedStatement(
-      await duckdb.prepare(this.connection, sql)
-    );
+    const prepared = await this.createPrepared(sql);
     this.preparedStatements.add(prepared);
     return prepared;
   }
+  private async createPrepared(sql: string): Promise<DuckDBPreparedStatement> {
+    return new DuckDBPreparedStatement(
+      await duckdb.prepare(this.connection, sql)
+    );
+  }
   public async extractStatements(
     sql: string
   ): Promise<DuckDBExtractedStatements> {