Connection pooling for serverless in NextJS - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the database client for connection pooling.

NextJS

import { [1] } from '@vercel/postgres';

Drag options to blanks, or click blank then click option'

Apool

BcreateClient

Cconnect

DClient

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'createClient' instead of 'pool' causes no pooling.

Using 'connect' is incorrect as it's not exported here.

The 'pool' export from '@vercel/postgres' is used to manage connection pooling in serverless Next.js apps.

2fill in blank

medium

Complete the code to acquire a client connection from the pool.

NextJS

const client = await pool.[1]();

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Aconnect

BgetClient

Cacquire

Dopen

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'getClient' or 'acquire' causes runtime errors as these methods don't exist.

The 'connect' method is used to get a client connection from the pool.

3fill in blank

hard

Fix the error in releasing the client connection back to the pool.

NextJS

await client.[1]();

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Aclose

Brelease

Cend

Ddisconnect

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'close' or 'end' closes the connection permanently, breaking pooling.

The 'release' method returns the client to the pool for reuse.

4fill in blank

hard

Fill both blanks to create a query and release the client properly.

NextJS

const result = await client.[1]('SELECT NOW()');
await client.[2]();

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Aquery

Brelease

Cexecute

Dclose

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'execute' instead of 'query' causes errors.

Using 'close' instead of 'release' breaks pooling.

Use 'query' to run SQL and 'release' to return the client to the pool.

5fill in blank

hard

Fill all three blanks to implement a safe query with try-finally for connection pooling.

NextJS

const client = await pool.[1]();
try {
  const result = await client.[2]('SELECT * FROM users');
  return result.rows;
} finally {
  await client.[3]();
}

Drag options to blanks, or click blank then click option'

Aconnect

Bquery

Crelease

Dclose

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to release client causes connection leaks.

Using 'close' instead of 'release' breaks pooling.

Acquire client with 'connect', run query with 'query', and release client with 'release' in finally block.