backend-queries

Write efficient and secure database queries following best practices for SQL injection prevention, N+1 query optimization, and performance for PostgreSQL (Bun.sql, Prisma, Supabase) and Firestore. Use this skill when writing or modifying database queries, implementing data fetching logic, working with ORMs (Prisma, TypeORM, Entity Framework), using Bun.sql native driver, querying Firestore collections, or implementing caching strategies. Apply when working on service files (services/*.ts, repositories/*.ts, *Service.cs), query builder implementations, data access layers, or any code that fetches or manipulates data. This skill ensures parameterized queries to prevent SQL injection (never interpolate user input), eager loading to prevent N+1 problems, selective column fetching (no SELECT *), strategic indexing on WHERE/JOIN/ORDER BY columns, transactions for related operations, query timeouts for performance, caching expensive queries, prepared statements with Bun.sql for repeated queries, and query-driven mod

// tip: Run this command in your terminal to install the skill