Firstly, in a query as follows there is no need for the second DISTINCT:
select distinct * from table1 where column1 in (select distinct column1 from table 1).
Secondly, you may be able to GROUP BY column1, if the result you want returned for column2 is either the MIN or the MAX value in the rows that match the grouped column.
My thought question: Have you ever been told that your query runs too fast?
My advice:
INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.
Need to UNPIVOT? Why not CROSS APPLY VALUES instead?[/url]
Since random numbers are too important to be left to chance, let's generate some![/url]
Learn to understand recursive CTEs by example.[/url]
[url url=http://www.sqlservercentral.com/articles/St