Batch Processing with DataLoader

Solve N+1 query problems using the DataLoader pattern. This skill provides utilities for batching database queries, API calls, or any expensive operations.

Problem: N+1 Query

// BAD: N+1 queries (1 for list + N for each item)
const users = await db.query('SELECT * FROM users');
for (const user of users) {
  const posts = await db.query('SELECT * FROM posts WHERE user_id = ?', [user.id]);
  user.posts = posts;
}
// Total queries: 1 + N (where N = number of users)

Solution: DataLoader Pattern