MySQL行(记录)的操作(二) -- 多表查询 数据的准备 #建表 create table department( id int, name varchar(20) ); create table employee( id int primary key auto_increment, name varchar(20), sex enum('male','female') not null default 'male', age int, dep_id int ); #插入数据 insert…
mysql; +----+-----------+------+-----+------------+---------+--------------+------------+--------+-----------+ | id | name | sex | age | hire_date | post | post_comment | salary | office | depart_id | +----+-----------+------+-----+------------+-----…
统计MySQL中某个数据库中有多少张表 SELECT count(*) TABLES, table_schema FROM information_schema.TABLES where table_schema = '数据库名称' GROUP BY table_schema; 统计MySQL中某个数据库中表记录数 use information_schema; select table_name,table_rows from tables where TABLE_SCHE…
