Ray Laubert (6/26/2009)
The question then becomes does SQL treat the selection of covering indexes the same way it does the selection of candidate indexes. left to right and stopping at the first mismatch or does it just look for all the columns required before determining if it is a covering index.
The order of include columns does not matter. Only the order of key columns matters and then only for seek predicates.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability