what is faster query (select name .... or select top(1) name

Question

what is faster query ?

select Name from Worker

or

select TOP(1) Name from Worker

I have 1,000,000 records

thank's in advance

Answer 1

If you don't have an ORDER BY or a DISTINCT, SELECT TOP(1) Name FROM Worker is faster.

The reason for this is that if you do happen to have an ORDER BY or a DISTINCT, the query has to go through the entire table to sort and filter out unwanted results. If it's a straight SELECT TOP, however, it can go to the first page, take the first row, and be done with it very quickly.