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MySQL多表關(guān)聯(lián)數(shù)據(jù)同時(shí)刪除sql語(yǔ)句 有需要的朋友可參考。DELETE刪除多表數(shù)據(jù)，怎樣才能同時(shí)刪除多個(gè)關(guān)聯(lián)表的數(shù)據(jù)呢？這里做了深入的解釋：代碼如下 復(fù)制代碼1    delete from t1 where 條件2    delete t1 from t1 where 條件3    delete t1 from t1,t2 where 條件4    delete t1,t2 from t1,t2 where 條件category（欄目信息表）和news（新聞數(shù)據(jù)表）。category中的id（欄目編號(hào)）字段作為該表的主鍵（primary key）.唯一標(biāo)識(shí)了一個(gè)欄目的信息。news 中的id字段作為該表的主鍵（primary key）.唯一標(biāo)識(shí)了一個(gè)欄目的信息。category_id（欄目編號(hào)）字段與category表的id字段相關(guān)聯(lián)。1.SQL刪除語(yǔ)句代碼如下 復(fù)制代碼delete category,news from category left join news on category.id = news.category_id1、從數(shù)據(jù)表t1中把那些id值在數(shù)據(jù)表t2里有匹配的記錄全刪除掉1代碼如下 復(fù)制代碼DELETE t1 FROM t1,t2 WHERE t1.id=t2.id 或 DELETE FROM t1 USING t1,t2 WHERE t1.id=t2.id2、從數(shù)據(jù)表t1里在數(shù)據(jù)表t2里沒(méi)有匹配的記錄查找出來(lái)并刪除掉1代碼如下 復(fù)制代碼DELETE t1 FROM t1 LEFT JOIN T2 ON t1.id=t2.id WHERE t2.id IS NULL 或 DELETE FROM t1,USING t1 LEFT JOIN T2 ON t1.id=t2.id WHERE t2.id IS NULL3、 從兩個(gè)表中找出相同記錄的數(shù)據(jù)并把兩個(gè)表中的數(shù)據(jù)都刪除掉1代碼如下 復(fù)制代碼DELETE t1,t2 from t1 LEFT JOIN t2 ON t1.id=t2.id WHERE t1.id=25注意此處的delete t1,t2 from 中的t1,t2不能是別名如：1代碼如下 復(fù)制代碼delete t1,t2 from table_name as t1 left join table2_name as t2 on t1.id=t2.id where table_name.id=25在數(shù)據(jù)里面執(zhí)行是錯(cuò)誤的（MYSQL 版本不小于5.0在5.0中是可以的）上述語(yǔ)句改 寫(xiě)成1代碼如下 復(fù)制代碼delete table_name,table2_name from table_name as t1 left join table2_name as t2 on t1.id=t2.id where table_name.id=25MySQL多表關(guān)聯(lián)數(shù)據(jù)同時(shí)刪除sql語(yǔ)句 有需要的朋友可參考。DELETE刪除多表數(shù)據(jù)，怎樣才能同時(shí)刪除多個(gè)關(guān)聯(lián)表的數(shù)據(jù)呢？這里做了深入的解釋：代碼如下 復(fù)制代碼1    delete from t1 where 條件2    delete t1 from t1 where 條件3    delete t1 from t1,t2 where 條件4    delete t1,t2 from t1,t2 where 條件category（欄目信息表）和news（新聞數(shù)據(jù)表）。category中的id（欄目編號(hào)）字段作為該表的主鍵（primary key）.唯一標(biāo)識(shí)了一個(gè)欄目的信息。news 中的id字段作為該表的主鍵（primary key）.唯一標(biāo)識(shí)了一個(gè)欄目的信息。category_id（欄目編號(hào)）字段與category表的id字段相關(guān)聯(lián)。1.SQL刪除語(yǔ)句代碼如下 復(fù)制代碼delete category,news from category left join news on category.id = news.category_id1、從數(shù)據(jù)表t1中把那些id值在數(shù)據(jù)表t2里有匹配的記錄全刪除掉1代碼如下 復(fù)制代碼DELETE t1 FROM t1,t2 WHERE t1.id=t2.id 或 DELETE FROM t1 USING t1,t2 WHERE t1.id=t2.id2、從數(shù)據(jù)表t1里在數(shù)據(jù)表t2里沒(méi)有匹配的記錄查找出來(lái)并刪除掉1代碼如下 復(fù)制代碼DELETE t1 FROM t1 LEFT JOIN T2 ON t1.id=t2.id WHERE t2.id IS NULL 或 DELETE FROM t1,USING t1 LEFT JOIN T2 ON t1.id=t2.id WHERE t2.id IS NULL3、 從兩個(gè)表中找出相同記錄的數(shù)據(jù)并把兩個(gè)表中的數(shù)據(jù)都刪除掉1代碼如下 復(fù)制代碼DELETE t1,t2 from t1 LEFT JOIN t2 ON t1.id=t2.id WHERE t1.id=25注意此處的delete t1,t2 from 中的t1,t2不能是別名如：1代碼如下 復(fù)制代碼delete t1,t2 from table_name as t1 left join table2_name as t2 on t1.id=t2.id where table_name.id=25在數(shù)據(jù)里面執(zhí)行是錯(cuò)誤的（MYSQL 版本不小于5.0在5.0中是可以的）上述語(yǔ)句改 寫(xiě)成1代碼如下 復(fù)制代碼delete table_name,table2_name from table_name as t1 left join table2_name as t2 on t1.id=t2.id where table_name.id=25