PostgresEngine

import { Column, PostgresEngine, PostgresEngineArgs } from "@langchain/google-cloud-sql-pg";

const pgArgs: PostgresEngineArgs = {
   user: "db-user",
   password: "password"
}

const engine: PostgresEngine = await PostgresEngine.fromInstance(
 "project-id",
 "region",
 "instance-name",
 "database-name",
 pgArgs
);