使用平【not】in的子查询
语法结构：
Operand comparison_operator [not] in (subquery)
=any 运算符与in等效
！=all或<>all运算符与not in等效
使用【not】exists的子查询
如果子查询返回任意行，exists将返回true；否则为false
INSERT [INTO] tbl_name SET col_name={exprDEFAULT},...//可以使用子查询
INSERT [INTO] tbl_name [(col_name,...)] SELECT ...//将查询结果写入数据表
Eg：
INSERT INTO table_name [(column_name)] SELECT column_name2 FROM table_name2 GROUP BY column_name3;
CREATE TABLE IF NOT EXISTS tdb_goods_cates(
cate_id SMALLINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
cate_name VARCHAR(40) NOT NULL
);
SELECT goods_cate FROM tdb_goods GROUP BY goods_cate; //列出所有品牌的分组
DESC tdb_goods_cates; //降序显示出tdb_goods_cates表中的项目名称
INSERT tdb_goods_cates(cate_name) SELECT goods_cate FROM tdb_goods GROUP BY goods_cate;//在表tdb_goods_cates中插入tdb_goods中的goods_cate的分组