正确使用 RowCount

Question

我的存储过程中有以下内容：

DECLARE @CustomerNumber nvarchar(50)

SELECT TOP 200 
    C.CustomerNumber as SourceSystemId,
    C.CustomerName,
    AccountManager,
    C.CustomerId        
FROM 
    Customer C WITH(NOLOCK, index (UQ_Customer_CustomerNumber))
LEFT JOIN 
    CustomerQuotingPreference cp WITH(NOLOCK)ON cp.CustomerId = C.CustomerId
WHERE  
    (C.CustomerName LIKE ('%1725614%') 
    OR C.CustomerNumber LIKE ('%' + CONVERT(VARCHAR(61), '1725614' ) +'%'))         
ORDER BY
    C.CustomerName

IF @@ROWCOUNT = 0  
BEGIN 
    SELECT DISTINCT 
        @CustomerNumber= C.CustomerNumber
    FROM
        [IFO].dbo.PricedealProposal PP
    JOIN
        IFO.dbo.OrderQuote OQ ON PP.OrderQuoteId = OQ.OrderQuoteId      
    JOIN
        Customer C ON C.CustomerId = OQ.CompanyId
    WHERE
        PP.PriceDealProposalId = '1725614' 

    EXEC [dbo].[Customer_ListCustomerDetailsByCustomerNumber] @searchString = @CustomerNumber   
END

当我运行这个时，我得到了两个选择的结果，而不是最后一个：

如何根据满足的条件仅从其中一个选择中获取结果？

Answer 1

肯定有很多不同的方法可以做到这一点。想到的一种方法是您可以将第一次选择的结果放入表变量或临时表中。然后根据行数大于 0 或 if 存在 select 1 from temp table type of check 执行 If/Else，最后根据 if/else 检查只执行一个选择，要么选择 off该临时表/变量或选择关闭选项 B。

Answer 2

怎么样...

DECLARE @CustomerNumber nvarchar(50)
IF NOT EXISTS(
        SELECT TOP 200 C.CustomerNumber as SourceSystemId
            ,C.CustomerName             
            ,AccountManager
            ,C.CustomerId       
        FROM Customer C WITH(NOLOCK, index (UQ_Customer_CustomerNumber))
        LEFT JOIN CustomerQuotingPreference cp WITH(NOLOCK)ON cp.CustomerId = C.CustomerId
        WHERE  (C.CustomerName like ('%1725614%') 
            OR C.CustomerNumber like ('%' + CONVERT(VARCHAR(61),'1725614' ) +'%'))
)
        BEGIN 
            --NOTE TOP 1 HERE!
            select TOP 1 @CustomerNumber= C.CustomerNumber
            from [IFO].dbo.PricedealProposal PP
            join IFO.dbo.OrderQuote OQ
            on PP.OrderQuoteId = OQ.OrderQuoteId        
            join Customer C
            on C.CustomerId= OQ.CompanyId
            Where PP.PriceDealProposalId = '1725614' 

            EXEC [dbo].[Customer_ListCustomerDetailsByCustomerNumber] @searchString = @CustomerNumber   
        END
        ELSE
        BEGIN
            SELECT TOP 200 C.CustomerNumber as SourceSystemId
                ,C.CustomerName             
                ,AccountManager
                ,C.CustomerId       
            FROM Customer C WITH(NOLOCK, index (UQ_Customer_CustomerNumber))
            LEFT JOIN CustomerQuotingPreference cp WITH(NOLOCK)ON cp.CustomerId = C.CustomerId
            WHERE  (C.CustomerName like ('%1725614%') 
                OR C.CustomerNumber like ('%' + CONVERT(VARCHAR(61),'1725614' ) +'%'))
        END