MySQL 8 Administrator???s Guide

Real-world scenario

MySQL query optimization is referred to as improving the time of query execution. For example, when a query is not performing well means that the query is taking a longer time than expected for execution. The time of the query execution is important but there are other matrices as well that are used to measure performance. This section explains what should be measured and how it should be done as precisely as possible.

The following question arises: why should we optimize the query? Does it really require optimization if it only takes a hundredth of a second? Yes, it does require optimization unless the query is executed rarely. We should optimize the queries that are most expensive.

Let's discuss a real-time example. ...