What metric do you use to measure data retrieval speed from a database?

The speed of data retrieval from a database is usually measured using the response time (latency) — the amount of time that passes from sending a request to receiving the result.

To measure this, you can use:

• The execution time of a specific query (for example, using built-in database profiling tools or timers in the code).
• The number of input/output (I/O) operations affecting the delay.
• Throughput — the number of requests processed per unit of time.

In Go, you can measure the query execution time as follows:

start := time.Now()
rows, err := db.Query("SELECT * FROM users WHERE id = ?", userID)
// handle err and rows
elapsed := time.Since(start)
fmt.Printf("Query took %s\n", elapsed)

Thus, the main indicator is the response time, which helps evaluate performance and optimize database operations.