Deepak M Deepak M - 30 days ago 16
SQL Question

MS SQL: How union works inside if exists condition?

Can anyone explain how union works inside if exists? My code is below.

if exists(select top 1 ShoppingCartNo from tbSupplierLineItem
where BidSummaryDueDate>CONVERT(date,getdate()) and ShoppingCartNo=@SC
select top 1 ShoppingCartNo from Protrac_Archieve.dbo.tbSupplierLineItem
where BidSummaryDueDate>CONVERT(date,getdate()) and ShoppingCartNo=@SC)
SQL statements

Answer Source

It first combines the result sets of two select queries inside if exists statement and then checks for the existence of any record from those queries.