比较2列和删除不匹配

Question

$db->query("DELETE FROM probid_auction_media 
WHERE auction_id NOT IN SELECT DISTINCT auction_id FROM probid_auctions"); 

这是我使用的代码，我希望做的是列auction_id从probid_auction_media从probid_auctions列auction_id比较和删除从没有数学任何的人probid_auction_media

Answer 1

您需要括号：

DELETE FROM probid_auction_media 
WHERE auction_id NOT IN 
     (SELECT auction_id FROM probid_auctions) 

Answer 2

你错过了括号。另外，DISTINCT可能不是必要的：

DELETE FROM probid_auction_media 
    WHERE auction_id NOT IN (SELECT auction_id FROM probid_auction)