1.内连接
2.左连接
3.右连接
4.多表连接
SELECT goods_id,goods_name,cate_name,brand_name,goods_price FROM tdb_goods AS g INNER JOIN tdb_goods_cates AS c ON g.cate_id = c.cate_id ->INNER JOIN tdb_brands AS b ON g.brand_id = b.brand_id\G;