84669 person learning
152542 person learning
20005 person learning
5487 person learning
7821 person learning
359900 person learning
3350 person learning
180660 person learning
48569 person learning
18603 person learning
40936 person learning
1549 person learning
1183 person learning
32909 person learning
我知道USE INDEX，IGNORE INDEX，FORCE INDEX这3个命令，分别是添加 USE INDEX 来提供你希望 MySQ 去参考的索引列表，就可以让 MySQL 不再考虑其他可用的索引。IGNORE INDEX让 MySQL 忽略一个或者多个索引。FORCE INDEX为强制 MySQL 使用一个特定的索引。哪有什么命令可以让mysql同时使用两个索引来进行查询吗？
光阴似箭催人老，日月如移越少年。
What does it mean? Do you want a joint index? Something like this:
alter table test add INDEX `sindex` (`aaa`,`bbb`,`ccc`)
aaa, bbb, ccc are the three columns of the test table
Mysql will merge the indexes. For relevant information in the manual, please seehttp://dev.mysql.com/doc/refman/5.6/en/index-merge-optimization.html
http://dev.mysql.com/doc/refman/5.6/en/index-merge-optimization.html
The answer above is to create a composite primary key. If you query, select group by a,b
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
What does it mean? Do you want a joint index? Something like this:
aaa, bbb, ccc are the three columns of the test table
Mysql will merge the indexes. For relevant information in the manual, please see
for details.http://dev.mysql.com/doc/refman/5.6/en/index-merge-optimization.htmlThe answer above is to create a composite primary key. If you query, select group by a,b