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這幾天都在學(xué)mysql，中午被一道題卡住了
題為：實(shí)現(xiàn)goods表,category表,brand表,3表連接查詢,得出以下字段
| goods_id |
cat_id |
cat_name |
brand_id |
brand_name |
goods_name |
里面有g(shù)oods、category、brand三張表，兩表聯(lián)查是會(huì)的
- <span style="font-family:'Microsoft YaHei';font-size:12px;">select goods_id,goods.cat_id,cat_name,goods.brand_id,goods_name from goods left join category on goods.cat_id = category.cat_id</span>
- <span style="font-family:'Microsoft YaHei';font-size:12px;">select goods_id,goods.cat_id,cat_name,goods.brand_id,brand_name,goods_name from goods left join category on goods.cat_id = category.cat_id left join brand on goods.brand_id = brand.brand_id;</span>
- <span style="font-family:'Microsoft YaHei';font-size:12px;">select brand_name from (select goods_id,goods.cat_id,cat_name,goods.brand_id,goods_name from goods left join category on goods.cat_id = category.cat_id) as temp left join brand on goods.brand_id = brand.brand_id;</span>
- <span style="font-family:'Microsoft YaHei';font-size:12px;">goods left join category on goods.cat_id = category.cat_id</span>
之所以寫這個(gè)，一是提醒下自己以后不要又陷入思維定式了，二是，今天中午也上網(wǎng)查了下資料，可是滿意的卻沒(méi)有，于是就整理下，寫了下來(lái)，高手勿哂。
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