***** ## 創建 "商品分類" 表 ~~~ create table goods_cates( id int unsigned primary key auto_increment not null, name varchar(40) not null ); ~~~ * 查詢goods表中商品的種類 ~~~ select cate_name from goods group by cate_name; ~~~ * 將分組結果寫入到goods\_cates數據表 ~~~ insert into goods_cates (name) select cate_name from goods group by cate_name; ~~~ ### 同步表數據 * 通過goods\_cates數據表來更新goods表 ~~~ update goods as g inner join goods_cates as c on g.cate_name=c.name set g.cate_name=c.id; ~~~