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PostgreSQL Pool With Parameterized Queries

Query PostgreSQL through a pg pool with always-parameterized statements, statement timeouts, idle client recycling, and pool sizing guidance.

JavascriptNodeData Fetching

Code

snippet
import pg from 'pg';

const pool = new pg.Pool({
  connectionString: process.env.DATABASE_URL,
  max: 20,
  idleTimeoutMillis: 30_000,
  connectionTimeoutMillis: 5_000,
  statement_timeout: 10_000,
  query_timeout: 12_000,
  application_name: 'orders-service',
});

pool.on('error', (err) => console.error('idle client error:', err.message));

async function listRecentOrders(customerId, limit = 25) {
  const { rows, rowCount } = await pool.query(
    'SELECT id, total, created_at FROM orders WHERE customer_id = $1 ORDER BY created_at DESC LIMIT $2',
    [customerId, limit],
  );
  return { rows, rowCount };
}

async function withTransaction(fn) {
  const client = await pool.connect();
  try {
    await client.query('BEGIN');
    const result = await fn(client);
    await client.query('COMMIT');
    return result;
  } catch (err) {
    await client.query('ROLLBACK');
    throw err;
  } finally {
    client.release();
  }
}

const recent = await listRecentOrders('c-812');
console.log('found', recent.rowCount, 'orders');
await pool.end();

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