【MySQL】MySQL查询、最左匹配原则、创建联合主键及通过联合主键查询

1、条件查询

https://blog.csdn.net/weixin_48171371/article/details/107826738

2、联表查询、排序等

https://blog.csdn.net/insist_to_learn/article/details/111935288?utm_medium=distribute.pc_relevant.none-task-blog-baidujs_title-3&spm=1001.2101.3001.4242

3、连接查询

https://www.cnblogs.com/yhongji/p/9820962.html

4、最左匹配原则

https://blog.csdn.net/adorablewolf/article/details/88318163?utm_medium=distribute.pc_relevant.none-task-blog-baidujs_utm_term-0&spm=1001.2101.3001.4242

5、创建联合主键及通过联合主键查询

https://www.cnblogs.com/chenjfblog/p/7593509.html

https://bbs.csdn.net/topics/391814929?page=1

5、LEFT JOIN 关键字

浅析：https://www.runoob.com/sql/sql-join-left.html

图解：https://zhuanlan.zhihu.com/p/59656673