pg¶

This page explains how to use ts-sql-query with the pg driver. It covers two approaches: using a connection pool or using a single connection directly.

Supported databases

PostgreSQL

Tested with

pg ^8.20.0

This information reflects the driver version pinned in this project's devDependencies and exercised by the CI suite. Other compatible versions may work but are not actively tested.

Do not share connections between requests

A ts-sql-query connection object — along with the query runner instances passed to its constructor — represents a dedicated connection to the database.

Therefore, you must not share the same connection object between concurrent HTTP requests. Instead, create a new connection object for each request, along with its own query runners.

Even if the query runner internally uses a connection pool, the ts-sql-query connection still represents a single active connection, acquired from the pool. It must be treated as such and never reused across requests.

Using a connection pool¶

Executes queries through a pg connection obtained from a pool.

import { Pool } from 'pg';
import { PgPoolQueryRunner } from "ts-sql-query/queryRunners/PgPoolQueryRunner";

const pool = new Pool({
    user: 'dbuser',
    host: 'database.server.com',
    database: 'mydb',
    password: 'secretpassword',
    port: 3211,
});

async function main() {
    const connection = new DBConnection(new PgPoolQueryRunner(pool));
    // Do your queries here
    connection // ...
}

Warning

If you want to allow to have nested transactions you must create the instance as new PgPoolQueryRunner(pool, {allowNestedTransactions: true})

Using a single connection¶

Executes queries through a dedicated pg connection.

import { Pool } from 'pg';
import { PgQueryRunner } from "ts-sql-query/queryRunners/PgQueryRunner";

const pool = new Pool({
    user: 'dbuser',
    host: 'database.server.com',
    database: 'mydb',
    password: 'secretpassword',
    port: 3211,
});

async function main() {
    const pgConnection = await pool.connect();
    try {
        const connection = new DBConnection(new PgQueryRunner(pgConnection));
        // Do your queries here
        connection // ...
    } finally {
        pgConnection.release();
    }
}

Warning

If you want to allow to have nested transactions you must create the instance as new PgQueryRunner(pgConnection, {allowNestedTransactions: true})