CSS Grid provides two-dimensional layout control for rows and columns simultaneously. I use display: grid to create grid containers. The grid-template-columns and grid-template-rows properties define track sizes. The fr unit distributes available spac

Flexbox provides one-dimensional layout for rows or columns. I use display: flex on containers to enable flexbox. The flex-direction property controls main axis direction (row, column, row-reverse, column-reverse). The justify-content property aligns

Meta tags provide metadata about HTML documents for search engines and social media. I use <meta name="description"> for search result snippets (150-160 characters). The viewport meta tag ensures responsive design on mobile devices. Open Graph t

HTML5 form validation uses attributes like required, pattern, min, max, and type to validate input. I leverage native validation before JavaScript. The <label> element associates text with inputs for accessibility. Input types like email, tel, u

Semantic HTML uses meaningful elements like <header>, <nav>, <main>, <article>, and <footer> instead of generic <div> tags. I structure content with proper heading hierarchy (<h1> to <h6>). Semantic mark

Query debugging identifies performance and correctness issues. I use EXPLAIN ANALYZE to understand execution plans. Slow query logs reveal problematic queries. pgstatstatements tracks query statistics. Understanding sequential scans vs index scans hel

Database best practices ensure reliability and performance. I follow normalization principles—minimize redundancy. Use appropriate indexes—not too many, not too few. Implement constraints for data integrity. Choose correct data types for efficiency. R

Query plan caching improves performance by reusing execution plans. I use prepared statements to parse once, execute many times. PostgreSQL caches plans after 5 executions. Plan invalidation occurs when statistics change. Generic plans vs custom plans

Database design patterns solve recurring problems. I use the Repository pattern to abstract data access. Active Record maps objects to tables. Unit of Work tracks changes for batch commits. Identity Map caches loaded entities. The Specification patter

Database locks ensure data consistency in concurrent access. I understand lock types—row, table, advisory. Shared locks allow concurrent reads. Exclusive locks prevent all access. Understanding lock granularity prevents contention. Deadlocks occur whe

Database testing ensures schema and queries work correctly. I use transactions for test isolation—rollback after each test. Test fixtures provide consistent data. Factory patterns generate test data programmatically. Understanding schema migrations in

Foreign Data Wrappers (FDW) query external data sources as tables. I use postgresfdw for remote PostgreSQL databases. filefdw reads CSV files. mysql_fdw connects to MySQL. Understanding FDW limitations prevents surprises. Predicates push down to remot