Logging to measure execution time.

进行日志记录以测试执行时间。

Sort the tests by rough execution time.

按照大概的执行时间给测试排序。

This is ideal if execution time allows.

如果执行时间允许的话，这样做是理想的。

Step 1.1: Examine the query execution time.

步骤1.1：检查查询执行时间。

This also reduces overhead at execution time.

这样还可以减少执行时的开销。