Field id is of type int
select * from table where id="1";
select * from table where id=1;
I seem to be the same through explain, but why is there a statement similar to the first line in the slow query? In addition, there are some sql in the slow query through the explain test type is ref, scan lines are not many, and so on, but also used the index, why is it still a slow query?
there is a process of implicit type conversion, which of course consumes computation.
MySQL:: MySQL 5.7 Reference Manual:: 12.2 Type Conversion in Expression Evaluation: https://dev.mysql.com/doc/ref.
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