When you acquire a connection either using withConnection or getConnection you can specify config options which will be applied to the connection.

await DB.withConnection(
  {
      postgresConfig: { work_mem: "512MB" },
  },
  async (conn) => {
    await conn.begin();

    await conn.query("SELECT 1;");

    await conn.commit();
  }
);

The SQL executed on the connection would be

SET work_mem = '512MB';

BEGIN;

SELECT 1;

COMMIT;

These settings will stay on the Postgres connection after it gets released back to the pool so they might affect connections you will acquire in the future.

Default connection settings

You can specify default options that should be passed to every connection when its acquired from the pool.

new PostgresClient({
  defaultConnectionOptions: {
    collectSql: true,
    postgresConfig: { work_mem: "512MB" },
  },
});

Concepts

Changing Postgres config

Default connection settings

​Default connection settings

Default connection settings