Which is better: Distinct or Group By

Question

Which is more efficient?

SELECT  theField
FROM    theTable
GROUP BY theField

or

SELECT  DISTINCT theField
FROM    theTable
         


        

Answer 1

Doesn't matter, it results in the same execution plan. (at least for these queries). These kind of questions are easy to solve, by enabling query analyzer or SSMS to show the execution plan and perhaps the server trace statistics after running the query.