current position:Home>The index is not triggered when MySQL uses the sum function

The index is not triggered when MySQL uses the sum function

2022-02-03 01:34:41 CSDN Q & A

img

createtime It's the index , But the query sum I didn't use .
If using count(*), You use indexes .
Why, please , What do I do ?




Refer to the answer 1:

Index failed




Refer to the answer 2:

copyright notice
author[CSDN Q & A],Please bring the original link to reprint, thank you.
https://en.primo.wiki/2022/02/202202030134405645.html

Random recommended