EXPLAIN command function

When our website or interface is accessed more and more frequently, if our related SQL statements take a long time to execute, it will easily cause the website or interface to respond slowly. Then using the explain statement, we can clearly understand We know how MySQL executes our SQL statement, how many records are queried in total when executing a certain query statement, what tables are used and the link order of multiple tables, what indexes are used in the query, and other information. With this information, we can optimize our database based on multiple executions and analysis, build indexes where the index should be built, and delete indexes that should be deleted.

The above is the detailed content of EXPLAIN command function. For more information, please follow other related articles on the PHP Chinese website!