Sql server 在SQL Server中更新Select Case语句：

我已经编写了下面的更新语句来更新PLN_DU_供应商表的StatusID

UPDATE 
PLN_DU_Vendor
SET
    PLN_DU_Vendor.StatusID = 2
FROM
    PLN_DU_Vendor 
INNER JOIN PMT_RFDDetail D ON PLN_DU_Vendor.DUID = D.DUID
INNER JOIN PMT_RFDHeader H ON H.RFDID = D.RFDID AND PLN_DU_Vendor.VendorID = H.VendorID
INNER JOIN PLN_LASCO_Header LH ON LH.LASCOID = H.LASCOID AND LH.ReleaseID = PLN_DU_Vendor.ReleaseID
AND PLN_DU_Vendor.VendorDUQuantity = (D.DespatchQuantity + ISNULL(PLN_DU_Vendor.RFDQuantity, 0))
WHERE
     H.RFDID = 10

如果条件

PLN_DU_Vendor.VendorDUQuantity = (D.DespatchQuantity + ISNULL(PLN_DU_Vendor.RFDQuantity, 0))

---

失败，我需要将StatusID更新为1。如何在同一update select语句中执行此操作。

看起来您需要将条件作为

CASE

语句从

连接

移动到赋值：

UPDATE 
PLN_DU_Vendor
SET
    PLN_DU_Vendor.StatusID = CASE 
    WHEN PLN_DU_Vendor.VendorDUQuantity = (D.DespatchQuantity + ISNULL(PLN_DU_Vendor.RFDQuantity, 0))
    THEN 2
    ELSE 1
    END
FROM
    PLN_DU_Vendor 
INNER JOIN PMT_RFDDetail D ON PLN_DU_Vendor.DUID = D.DUID
INNER JOIN PMT_RFDHeader H ON H.RFDID = D.RFDID AND PLN_DU_Vendor.VendorID = H.VendorID
INNER JOIN PLN_LASCO_Header LH ON LH.LASCOID = H.LASCOID AND LH.ReleaseID = PLN_DU_Vendor.ReleaseID
WHERE
     H.RFDID = 10

---

不能将任何浮点数与运算符

=

PLN_DU_Vendor.VendorDUQuantity = (D.DespatchQuantity + ISNULL(PLN_DU_Vendor.RFDQuantity, 0))

因此，最好是

PLN_DU_Vendor.VendorDUQuantity - (D.DespatchQuantity + ISNULL(PLN_DU_Vendor.RFDQuantity, 0)) < ERROR

PLN\u DU\u Vendor.VendorDUQuantity-（D.dispatchQuantity+ISNULL（PLN\u DU\u Vendor.RFDQuantity，0））

供应商的PLN.VendorDUQuantity的数据类型是什么？VendorDUQuantity、DispatchQuantity和RFDQuantity的数据类型为十进制（15,3）