一句普通的 SQL 语句SELECT * FROM GIRLS WHERE AGE BETWEEN 20 AND 24 AND BOYFRIEND IS NULL,也有很多内涵! 什么?没看出来?来,我来带你品品。 未限制返回的数量 这是个大问题啊,竟然没有设置 LIMIT 1,你是想找几个女朋友? 设置LIMIT 1 后MySQL 数据库引擎会在找到一条数据后停止搜索,而不是继
SQL语句: Select * FROM girls Where age Between 18 And 24 AND boyfriend Is Null 幽默图:
SELECT * FROM GIRLS WHERE AGE BETWEEN 20 AND 24 ... 阿粉最近看到一张图,如上所示,原本只是一个搞笑的图,但是在阿粉看来这分明是个渣男啊!一句普通的 SQL 语句SELECT * FROM GIRLS WHERE AGE BETWEEN 20 AND 24 AND BOYFRIEND IS NULL,也有很多内涵! 什么?没看出来?来,阿粉带你品品...
set b.boyfriend_id=2 where is null; # 右外连接修改多表记录 1234 1. 2. 3. 4. 5. 三.删除语句 方式一:delete 语法: 1.单表的删除★★★ delete from 表名 where 筛选条件 2.多表的删除[补充] sql92语法: delete 表1/表2的别名 from 表1 别名,表2 别名 where 连接条件 and 筛选条件;sql99...
程序员的T恤--SQL要这样记,永世不忘;SELECT * FROM girls WHERE age Between 18 And 24 AND boyfriend Is Null
select last_name, departments.department_name from employees as e, departments where commission_pct is not null and e.department_id = departments.department_id; #案例2:查询城市名中第二个字符为o的部门名和城市名 select d.department_name, l.city from departments as d, locations as l where d....