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sql server - Diff between Top 1 1 and Select 1 in SQL Select Query

I have a general doubt in sql. What is actually "Top 1 1" will do ? What is the meaning of the below query ?

select top 1 1 from Worker W where not exists (select 1 from Manager M where M.Id = W.Id)

what is the diff between select "TOP 1 1" and "SELECT 1" in sql server query ?

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SELECT TOP 1 Means Selecting the very 1st record in the result set

SELECT 1 Means return 1 as the result set

SELECT TOP 1 1 FROM [SomeTable] WHERE <SomeCondition> Means if the condition is true and any rows are returned from the select, only return top 1 row and only return integer 1 for the row (no data just the integer 1 is returned).


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