Question

我有以下SQL正在运行，

IF NOT EXISTS(SELECT 1 FROM [Batch] B 
INNER JOIN BatchProducts BP 
ON (B.ID = BP.BatchID) 
WHERE Bp.ID = @ID AND B.RetailerID = @RetailerID)
BEGIN
    RETURN; 
END
DELETE FROM BatchProducts WHERE  BatchProducts.ID = @ID;

但它由2个陈述组成。我想使用单个DELETE，条件是RetailerID必须在BatchProducts表中匹配。

Answer 1

你可以这样做：

DELETE FROM BatchProducts
WHERE BatchProducts.ID = @ID
AND EXISTS (SELECT * FROM [Batch] 
    WHERE [Batch].ID = BatchProducts.BatchID AND [Batch].RetailerID = @RetailerID)

Answer 2

是否有特殊原因需要检查它是否存在？

DELETE bp
FROM BatchProducts bp
    JOIN Batch b
        ON bp.BatchID = b.ID
WHERE bp.ID = @ID
AND b.RetailerID = @RetailerID

DELETE具有另一个表的条件的表的行

2 个答案: