Sql语句

#SELECT * FROM t_category,t_product;
#隐式内连接
#SELECT * FROM 表一,表二 WHERE c.cid=p.category_id;
#显式内连接
#SELECT * FROM t_category c INNER JOIN t_product p;
#SELECT * FROM t_category c INNER JOIN t_product p ON c.cid=p.category_id;
#左外连接（以左边表为主）
#SELECT * FROM t_category c LEFT OUTER JOIN t_product p ON c.cid=p.category_id;
#右外连接（以右边表为主）
#SELECT * FROM t_category c RIGHT OUTER JOIN t_product p ON c.cid=p.category_id;
#分组
#SELECT * FROM t_category c LEFT JOIN t_product p ON c.cid=p.category_id GROUP BY cname;

更新
UPDATE 表名 SET uname = “aa” WHERE id= 6
模糊查询
SELECT * FROM 表名 where uname like ‘%’“i”’%’ LIMIT 0,2
删除
DELETE FROM 表名 WHERE id = 12
添加
INSERT into 表名 VALUES (13,“ceshi”,123,null,null)