4

我有两张桌子：

A
id | name

和

B
id | name

在 B 表上，我创建查询以选择所有数据，其中 id 位于（...某些值），但是我如何在一个查询中选择此 B - id 并从 A 中删除，其中 A.id = B.id ？

我是 sql 新手……找不到如何在一个查询中组合所有内容……

*我必须在一些类似的查询中从 b 中选择，例如我的 b 查询：select * from B where somefieldinteger in (1,4,9,21,25) 并且 b.id 必须与 a* 进行比较

更新 这个抛出错误

delete `LINK_LA_TYP` FROM `LINK_LA_TYP` JOIN `LINK_ART` ON `LINK_LA_TYP`.LAT_LA_ID=`LINK_ART`.LA_ID JOIN `ARTICLES` ON `LINK_ART`.LA_ART_ID=`ARTICLES`.ART_ID WHERE (`ARTICLES`.ART_SUP_ID in (10008,10439,11005,10097,10669,11100,80,10912,10683,10675,10194,11196,1166,10730,10248,10870,11200,11059,247,10121,10911,489,10724,496,10093,10205,1318,10953,11199,11047,128,114,194,10865,11058,10345,1286,10667,10064,11077,10622,11205,10917,10344,495,10709,10954,10744,304,10957,10447,10764,10129,10862,10918,10731,11115,10095,10859,10580,1345,10177,10323,144,11182,10132,256,10941,58,10006,10017,10780,10765,10665,11110,10714,10224,750,10267,10179,10725,10774,11063,10868,10103,10676,10057,10649,255,10322,11022,309,10754,11121,10801,10018,11004,10245,146,11056,381,10781,10699,11120,11126,830,10240,11162,10436,10584,10342,10861,11190,10721,11171,10564,10545,94,10087,73,10755,10869,10547,10706,10346,444,426,10059,153,122,10674,64,113,11101,10231,10337,806,11117,10385,251,11188,491,11192,100,10792,10069,10864,11099,10246,10178,10758,10568,10230,10124,10384,10782,10726,384,10670,305,10763,10768,10585,10394,10552,498,10677,1348,168,10814,10582,10382,11093,11173,10381,427,441)) limit 50
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2 回答 2

9

delete像这样一起使用join：

mysql> create table a (id int);
mysql> insert into a values (1), (2), (3), (4);
mysql> create table b (id int);
mysql> insert into b values (2), (3);
mysql> delete a from a join b on a.id=b.id where b.id > 2;
mysql> select * from a;
+------+
| id   |
+------+
|    1 |
|    2 |
|    4 |
+------+

这可以扩展到任意数量的表，例如：

DELETE a 
FROM a 
JOIN b ON a.idA=b.idA 
JOIN c ON b.idB=c.idB;

a这将从那些b又被引用的记录中删除的所有记录中删除c。您也可以像这样添加 WHERE 子句：

DELETE a 
FROM a 
JOIN b ON a.idA=b.idA 
JOIN c ON b.idB=c.idB
WHERE a.status='done' AND
      b.status='open' AND
      c.status='open';

如果要限制要删除的行数，请执行以下操作：

DELETE a 
FROM a 
JOIN b ON a.idA=b.idA 
JOIN c ON b.idB=c.idB
LIMIT 500000;

如果要删除前 500000 行，则需要细化哪些行在前，因此需要在行之间建立一些排序。换句话说，您需要按某些标准对行进行排序，然后像这样限制：

DELETE a 
FROM a 
JOIN b ON a.idA=b.idA 
JOIN c ON b.idB=c.idB
ORDER BY a.something
LIMIT 500000;
于 2013-02-19T17:32:55.820 回答
1 
delete from A where exists (select 1 from B where A.id=B.id and B.criteria=true)

如果您省略 ... 并且 B.criteria=true 它将删除 A 中出现在 B 中的所有行；否则你删除任何符合你的标准的东西。

于 2013-02-19T17:32:27.890 回答