InstantForum.NET v2.9.0SQLServerCentralhttp://www.sqlservercentral.com/Forums/notifications@sqlservercentral.comSat, 25 May 2013 19:55:38 GMT20http://www.sqlservercentral.com/Forums/Topic401874-138-1.aspxSQL has to do meta-data lookups whether or not * is specified as it has to find the types and the column lengths.The reasons to not use select * are more around only retrieving the columns that you need and not returning all of them out of laziness. It's also so that code won't break if a new clumn is added to a table. finally, select * makes creating covering indexes almost impossible.Tue, 01 Jul 2008 00:10:47 GMTGilaMonsterhttp://www.sqlservercentral.com/Forums/Topic401874-138-1.aspxHere u can improve performance more by specifying column names rather than using "*". Because using * queries sys.columns system table for get the column names, which is unnecessary when we can simply specify them.But you have to remember to update SP when u change the table(columns).regards,http://onlinecoder.blogspot.com/Mon, 30 Jun 2008 23:47:34 GMTprasad_wickramasinghehttp://www.sqlservercentral.com/Forums/Topic401874-138-1.aspxComments posted to this topic are about the item [B]<A HREF="/scripts/Miscellaneous/30824/">Improving performance on joins to large tables.</A>[/B]Mon, 24 Sep 2007 01:36:14 GMTcadebryant