sql-server - SQL Server 计划缓存非常相似但不同的查询

Question

假设我有这样的查询：

SELECT COUNT(*) FROM Investors
WHERE 1=1  
AND 
(
    investerName IN (SELECT investerName FROM Assets WHERE Assets.CompanyID=Investors.CompanyID AND Assets.CompanyID = @companyID )
    OR investerName IN 
        (
            SELECT investerName FROM InvestmentEnrollments WHERE InvestmentEnrollments .CompanyID=Investors.CompanyIDAND InvestmentEnrollments .state IN (3,4) AND InvestmentEnrollments.CompanyID = @companyID         
        )
) 
AND Investors.CompanyID=@companyID

和另一个类似的查询：

SELECT COUNT(*) FROM Investors
WHERE 1=1  
AND 
(
    investerName IN (SELECT investerName FROM Assets WHERE Assets.CompanyID=Investors.companyID AND Assets.companyID = @companyID )
    OR investerName IN 
        (
            SELECT investerName FROM InvestmentEnrollments WHERE InvestmentEnrollments .companyID=Investors.companyID AND InvestmentEnrollments.state IN (3,4) AND InvestmentEnrollments.companyID = @companyID         
        )
) 
AND Investors.companyID=@companyID
AND Investors.userName = @someInvestorUserName

这两个查询非常相似，但第二个查询有额外的 where 谓词。那么在这种情况下 SQL Server 会做什么呢？它是否尝试将两者都放入同一个查询计划中？或者这些被认为是需要不同查询计划的两个不同查询？

Answer 1

查询不仅是不同的文本，而且在语义上也不同。这些是不同的查询，需要不同的执行计划。没有任何共同之处。