How did you perform query performance analysis?

For analyzing query performance, I used several approaches:

• Logging execution time: I added measurements before and after query execution to determine its duration.
• Profiling with tools: I used profilers (e.g., VisualVM, JProfiler) to identify bottlenecks.
• EXPLAIN PLAN in databases: For SQL queries, I analyzed execution plans to understand which operations take the most time.
• Caching and indexing: I checked whether indexes and cache are used and how they affect speed.

An example of simple timing measurement in Java:

long start = System.currentTimeMillis();
// execute query
long end = System.currentTimeMillis();
System.out.println("Query execution time: " + (end - start) + " ms");