Question

我写的这个查询SELECT sql，我需要实际删除它在输出中提供的所有数据，只是因为我无法在DELETE sql查询中正确转换它而不会遇到语法错误。

这里是查询：

SELECT *
FROM ps_attribute_impact AS at
LEFT JOIN
    ps_product_attribute AS prod_at
ON    at.id_product = prod_at.id_product
LEFT JOIN
    ps_product_attribute_combination AS comb
ON    prod_at.id_product_attribute = comb.id_product_attribute
WHERE comb.id_attribute='1' AND at.price='0.00' AND at.id_attribute='1' AND prod_at.price='0.00'

我已经尝试了这3个查询：

DELETE *
FROM ps_attribute_impact AS at
LEFT JOIN
    ps_product_attribute AS prod_at
ON    at.id_product = prod_at.id_product
LEFT JOIN
    ps_product_attribute_combination AS comb
ON    prod_at.id_product_attribute = comb.id_product_attribute
WHERE comb.id_attribute='1' AND at.price='0.00' AND at.id_attribute='1' AND prod_at.price='0.00'

和

DELETE ps_attribute_impact.*
FROM ps_attribute_impact AS at
LEFT JOIN
    ps_product_attribute AS prod_at
ON    at.id_product = prod_at.id_product
LEFT JOIN
    ps_product_attribute_combination AS comb
ON    prod_at.id_product_attribute = comb.id_product_attribute
WHERE comb.id_attribute='1' AND at.price='0.00' AND at.id_attribute='1' AND prod_at.price='0.00'

和

DELETE
FROM ps_attribute_impact AS at
LEFT JOIN
    ps_product_attribute AS prod_at
ON    at.id_product = prod_at.id_product
LEFT JOIN
    ps_product_attribute_combination AS comb
ON    prod_at.id_product_attribute = comb.id_product_attribute
WHERE comb.id_attribute='1' AND at.price='0.00' AND at.id_attribute='1' AND prod_at.price='0.00'

但我没有取得任何成功。任何人都可以帮助我吗？

Answer 1

multi table delete的正确语法是这样的

DELETE ps_attribute_impact 
  FROM ps_attribute_impact AS at 
  LEFT JOIN ps_product_attribute AS prod_at 
    ON at.id_product = prod_at.id_product 
  LEFT JOIN ps_product_attribute_combination AS comb 
    ON prod_at.id_product_attribute = comb.id_product_attribute 
 WHERE comb.id_attribute='1' 
   AND at.price='0.00' 
   AND at.id_attribute='1' 
   AND prod_at.price='0.00'

Answer 2

我不确定查询的逻辑，但join中delete的语法是：

DELETE at 
    FROM ps_attribute_impact at LEFT JOIN
         ps_product_attribute prod_at
         ON at.id_product = prod_at.id_product LEFT JOIN
         ps_product_attribute_combination comb
         ON prod_at.id_product_attribute = comb.id_product_attribute
    WHERE comb.id_attribute='1'  AND at.price = '0.00' AND at.id_attribute = '1' AND
          prod_at.price = '0.00';

因为您对where子句中的所有表进行了比较，所以left join实际上正在进行inner join。为清楚起见，您应将其更改为inner join。

SELECT（带LEFT JOIN）sql查询，以DELETE sql查询

2 个答案: