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How do you handle database connection pooling in a Node.js application?

Q: How do you handle database connection pooling in a Node.js application?

**TL;DR.** A **connection pool** keeps a set of **reusable** DB connections so requests **borrow and return** them instead of paying the cost of opening a new connection each time. You configure a **max size**, acquire timeout, and idle timeout, and **always release** connections (use a finally ) to avoid pool exhaustion. req A req B req C <path class='d-edge-accent' d='M112 85 H170' ma

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Explain how connection pooling optimizes communication with databases under heavy loads.

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Borrow + always release

import { Pool } from 'pg';
const pool = new Pool({ max: 10, idleTimeoutMillis: 30_000 });

async function getUser(id) {
  const client = await pool.connect();    // borrow
  try {
    const { rows } = await client.query('SELECT * FROM users WHERE id=$1', [id]);
    return rows[0];
  } finally {
    client.release();                      // ALWAYS return it
  }
}

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