What steps would you take to improve query performance?

To improve query performance in Go, you can follow these steps:

1. Profiling — first measure where the bottlenecks are (CPU, memory, I/O) using pprof.
2. Algorithm optimization — check if you can improve the query logic, reduce the number of operations.
3. Caching — cache results of frequent queries to avoid repeated computations.
4. Parallelization — if possible, parallelize processing using goroutines.
5. Database optimization — use prepared statements, indexes, minimize the number of queries.
6. Minimize allocations — avoid unnecessary memory allocations, use object pools (sync.Pool).

Example of using goroutines for parallel processing:

func processRequests(requests []Request) {
    var wg sync.WaitGroup
    for _, req := range requests {
        wg.Add(1)
        go func(r Request) {
            defer wg.Done()
            handleRequest(r)
        }(req)
    }
    wg.Wait()
}