Question

我有一个存储过程，它根据特定条件返回1或0的整数。它目前使用三个select语句，它将被多个位置的多个用户大量使用。必须有一种更有效的方法来做到这一点。

简而言之，查询首先检查订单上的所有清单项是否都已完成（单独的表），然后检查查看名为BreakOutGuest（位域）的字段是1还是0.取决于结果它检查总客人数是否大于0且订单总数为零。它会在所有这些条件上返回1或0。有没有更有效的方法来做到这一点？一个临时表所以我只需要打一次实际的表吗？以下是代码。

@ORDERID INT

AS
BEGIN

DECLARE @AUTO_CLOSE INT



    SET NOCOUNT ON;

--If all checklist items are marked complete move on, if not set @AUTO_CLOSE=0
IF NOT EXISTS(SELECT ORDERID FROM dbo.orderchecklistitems WHERE OrderID=@ORDERID AND CompletedON IS NULL)
BEGIN

--if BreakOutGuestFees is 1 only sum Guest_Count_1 + Guest_Count_2
IF EXISTS(SELECT * FROM dbo.Orders  WHERE (GuestCount_1 + GuestCount_2)>1 AND OrderTotal=0 AND BreakoutGuestFees=1)

BEGIN
SET @AUTO_CLOSE=1
END
ELSE 
SET @AUTO_CLOSE=0
--if BreakOutGuestFees is 0 only consider Guest_Count_1
IF EXISTS(SELECT * FROM dbo.Orders  WHERE (GuestCount_1)>1 AND OrderTotal=0 AND BreakoutGuestFees=0)
BEGIN
SET @AUTO_CLOSE=1
END
ELSE
SET @AUTO_CLOSE=0

END
ELSE 
SET @AUTO_CLOSE=0

END

Answer 1

如果没有错，您可以使用if，if逻辑将两个AND子句合并到单个OR子句中。试试这个。

IF NOT EXISTS(SELECT ORDERID
              FROM   dbo.orderchecklistitems
              WHERE  OrderID = @ORDERID
                     AND CompletedON IS NULL)
  BEGIN
      IF EXISTS(SELECT *
                FROM   dbo.Orders
                WHERE  ( ( GuestCount_1 + GuestCount_2 > 1
                           AND BreakoutGuestFees = 1 )
                          OR ( BreakoutGuestFees = 0
                               AND GuestCount_1 > 1 ) )
                       AND OrderTotal = 0
                       AND OrderID = @ORDERID)
        SET @AUTO_CLOSE=1
      ELSE
        SET @AUTO_CLOSE=0
  END
ELSE
  SET @AUTO_CLOSE=0

Answer 2

您只需一个查询即可执行选择检查

SELECT 
    (SELECT sum(1) FROM dual WHERE EXISTS (SELECT ORDERID FROM dbo.orderchecklistitems WHERE OrderID=@ORDERID AND CompletedON IS NULL)),
    (SELECT sum(1) FROM dual WHERE EXISTS (SELECT 1 FROM dbo.Orders  WHERE (GuestCount_1 + GuestCount_2)>1 AND OrderTotal=0 AND BreakoutGuestFees=1)),
    (SELECT sum(1) FROM dual WHERE EXISTS (SELECT 1 FROM dbo.Orders  WHERE (GuestCount_1)>1 AND OrderTotal=0 AND BreakoutGuestFees=0))
    INTO
    result1, result2, result3
    from dual

然后检查结果

Answer 3

DELCARE @AUTO_CLOSE INT = 0

IF NOT EXISTS(SELECT ORDERID
              FROM   dbo.orderchecklistitems
              WHERE  OrderID = @ORDERID
                     AND CompletedON IS NULL)
  BEGIN
      SET @AUTO_CLOSE = 
        (
            SELECT 
                CASE
                    WHEN (GuestCount_1 + GuestCount_2 > 1) AND BreakoutGuestFees = 0 THEN 1
                    WHEN (GuestCount_1 > 1 ) AND BreakoutGuestFees = 1 THEN 1
                    ELSE 0 END
            FROM dbo.orders
            WHERE OrderTotal = 0 AND OrderID = @orderID
        )
  END

更便宜的查询？

3 个答案: