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关于数据库查询问题

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Jun 23, 2016 pm 02:23 PM

SELECT a.*,b.`description`
FROM `1_sku_comparison` a,`1_product` b
WHERE a.`sku`='6007-00D'
and a.`item_code`=b.`item_code`

以上语句如果`1_product`没有相应的`item_code`就会导致整个语句结果为空，请问有什么方法，不要因为`1_product`.`item_code`没有相应的值，而导致整个结果为空，因为我主要是要查`1_sku_comparison`这个表的数据,1_product有没有没关系。

回复讨论(解决方案)

左连接
SELECT a.*,b.`description`
FROM `1_sku_comparison` a left join `1_product` b on a.`item_code`=b.`item_code`
WHERE a.`sku`='6007-00D'

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