kandi8027的博客

1.创建用户 CREATE USER john@127.0.0.1 --可以为localhost,也可制定域名 IDENTIFIED BY ‘1234’ 2.查看用户 SELECT * FROM mysql.user; 也可通过导航面板查看 3.删除用户 DROP USER bob@codewithmosh.com; 4.修改密码 修改john的密码 SET PASSWORD FOR john = ‘1234’; 修改当前登录用户密码 SET PASSWORD = ‘1234’; 也可通过导航面板更改 5

1.创建索引 CREATE INDEX idx_state ON customers（state）； –括号中键入想要放置索引的列名称 2.查看查询情况 EXPLAIN SELECT customer_id FROM customers; 3.查看索引 SHOW INDEXES IN customers; 也可以通过导航面板查看索引 主键 也成为了聚集索引（clustered index） 每当插入主键时，mysql会自动创建一个索引 每张表最多有一个聚集索引 4.生成表的统计信息 ANALYZE TA

笔记主要以列句形式来展现 1.选择SQL库 USE sql_store; 2.选择全部语句 SELECT * FROM customers; 3.选择部分语句 SELECT customer_id FROM customers; 4.条件筛选 SELECT * FROM customers WHERE customer_id = 1 5.排序 SELECT * FROM customers WHERE customer_id = 1 ORDER BY fist_name; 默认升序，降序需DESC 语句顺序