Core Relational Database Insights for Technical Interviews

Why Trace SQL Query Triggers?When executing SQL, databases optimize statements using execution plan graphs. Understanding logical sequence evaluation (FROM, JOIN, WHERE, GROUP BY, HAVING, SELECT, ORDER BY, LIMIT) allows candidates to avoid performance bottlenecks and optimize primary indices.

Common Relational Queries Developer TrapJunior developers frequently misunderstand the difference between WHERE and HAVING. WHERE filters records before grouping aggregations, whereas HAVING filters grouped rows. Applying WHERE filters on non-aggregated fields significantly reduces search spaces and query latency.