MySQL SHOW INDEXES
https://www.mysqltutorial.org/mysql-index/mysql-show-indexesTo get the index of a table, you specify the table name after the FROM keyword. The statement will return the index information associated with the table in the current database. You can specify the database name if you are not connected to any database or you want to get the index information of a table in a different database:
SQL INDEX - W3Schools
https://www.w3schools.com/mySQl/sql_ref_index.aspThe CREATE INDEX command is used to create indexes in tables (allows duplicate values). Indexes are used to retrieve data from the database very fast. The users cannot see the indexes, they are just used to speed up searches/queries. The following SQL creates an index named "idx_lastname" on the "LastName" column in the "Persons" table: