/*
查询库存大于20的信息
SELECT*FROM product WHERE stock>20;

*/

/*查询品牌为华为的商品信息
SELECT * FROM product WHERE brand=‘华为’;
*/

/查询金额在4000~ 6000之间的
SELECT * FROM product WHERE price>=4000 AND price <= 6000;
SELECTFROM product WHERE price BETWEEN 4000 AND 6000;
*/

/*查询库存为40 30 23 的商品信息
SELECT *FROM product WHERE stock=14 OR stock=30 OR stock=23;
SELECT *FROM product WHERE stock IN(14,30,23);
*/

/*查询库存为null的商品信息
SELECT *FROM product WHERE stock IS NULL;

*/

/*查询库存不为null的商品信息
SELECT *FROM product WHERE stock IS NOT NULL;

*/

/*查询名称以小米开头的商品信息
SELECT *FROM product WHERE NAME LIKE ‘小米%’;
*/

/*查询第二个名称是 为的商品信息
SELECT *FROM product WHERE NAME LIKE ‘_为%’;
*/

/*
查询名称是四个字符的商品信息
SELECT *FROM product WHERE NAME LIKE ‘____’;
*/

/*
查询名称包含电脑的商品信息
SELECT *FROM product WHERE NAME LIKE ‘%电脑%’;
*/