使用内部联接删除PostgreSQL

Question

DELETE B.* 
FROM   m_productprice B  
       INNER JOIN m_product C ON B.m_product_id = C.m_product_id 
WHERE  C.upc = '7094' AND B.m_pricelist_version_id = '1000020'

我收到以下错误PostgreSQL 8.2.11

ERROR:  syntax error at or near "B"
LINE 1: DELETE B.* from m_productprice B  INNER JOIN m_product C ON ...

我试着给

DELETE B from m_productprice B  INNER JOIN m_product C ON B....
 ERROR:  syntax error at or near "B"

我试着给

ERROR:  syntax error at or near "INNER"
LINE 1: DELETE from m_productprice B  INNER JOIN m_product C ON B.m_...

我的查询有什么问题？

Answer 1

DELETE 
FROM m_productprice B  
     USING m_product C 
WHERE B.m_product_id = C.m_product_id AND
      C.upc = '7094' AND                 
      B.m_pricelist_version_id='1000020';

要么

DELETE 
FROM m_productprice
WHERE m_pricelist_version_id='1000020' AND 
      m_product_id IN (SELECT m_product_id 
                       FROM m_product 
                       WHERE upc = '7094'); 

Answer 2

这对我有用:

DELETE from m_productprice
WHERE  m_pricelist_version_id='1000020'
       AND m_product_id IN (SELECT m_product_id
                            FROM   m_product
                            WHERE  upc = '7094'); 

Answer 3

与Postgres 9.1+一起使用的另一种形式是将公用表表达式与用于连接的USING语句相结合.

WITH prod AS (select m_product_id, upc from m_product where upc='7094')
DELETE FROM m_productprice B
USING prod C
WHERE B.m_product_id = C.m_product_id 
AND B.m_pricelist_version_id = '1000020';

Answer 4

只需使用INNER JOIN,LEFT JOIN或其他的子查询:

DELETE FROM m_productprice
WHERE m_product_id IN
(
  SELECT B.m_product_id
  FROM   m_productprice  B
    INNER JOIN m_product C 
    ON   B.m_product_id = C.m_product_id
  WHERE  C.upc = '7094' 
  AND    B.m_pricelist_version_id = '1000020'
)

优化查询,

• 使用NOT EXISTS代替IN
• 和WITH用于大型子查询

Answer 5

如果您有多个联接，则可以使用逗号分隔的USING语句：

DELETE 
FROM 
      AAA AS a 
USING 
      BBB AS b,
      CCC AS c
WHERE 
      a.id = b.id 
  AND a.id = c.id
  AND a.uid = 12345 
  AND c.gid = 's434sd4'

参考

Answer 6

基本上这里提到的所有内容都在文档中提到，但没有人具体说明具体内容。这就是当前 (v15) DELETE文档的内容：

笔记

PostgreSQL 允许您通过在子句中指定其他表来引用WHERE条件中其他表的列USING。例如，要删除给定制片人制作的所有电影，可以执行以下操作：

DELETE FROM films USING producers
 WHERE producer_id = producers.id AND producers.name = 'foo';

这里实质上发生的是电影和制片人之间的连接，所有成功连接的电影行都被标记为删除。这种语法不是标准的。更标准的方法是：

DELETE FROM films
 WHERE producer_id IN (SELECT id FROM producers WHERE name = 'foo');

在某些情况下，连接样式比子选择样式更容易编写或执行更快。