How can you check whether a MySQL query is making use of a Covering Index?

85 Views Asked by At

How can you check whether a MySQL query is making use of a Covering Index and getting all the data it needs solely from that Index?

1

There are 1 best solutions below

0
On BEST ANSWER

For an index only scan (covering index) MySQL shows 'Using index' in the Extra column.

http://use-the-index-luke.com/sql/explain-plan/mysql/operations