Somebody out here. please help me! I need this help for my b.tech final year project. I need to know how the cost calculations are done by mysql before tuning the indices, if it has the 'index tuning'. Otherwise, I need to know if there is anyway before materializing the index, cost of a particular query ,if an index set is materialized ,can be found out prior to the materialization. Please,please help me with this. I will be very grateful . Thanks in advance

I guess you are referring to "EXPLAIN". Have a look at that in the manual for your DB2 version and platform.

Or optimizer profiles:
IBM DB2 9.7 for Linux, UNIX and Windows Information Center

There is a "Virtual Index" facility in DB2 ZOS, where you can analyze an index before creating it. Here is the link, you can find detail.

DB2's Virtual Index Support

I vaguely remember , Quest Central provide the similar functionality for DB2 UDB .

I don't find same Virtual Index facility on DB2 UDB though. Does anybody know, aware of ?

db2advis, provide "what if " analysis in LUW world though not exactly in same manner as "Virtual Indexes".

this thread has had a 'interesting history'
started off life multi posted in MySQL & DB2 forums.
I interpreted it as a general request so moved it to the concepts forum
the original poster has no advised me that they would prefer it in the MySQL forum

most if not all of the responses are from posters in the DB2 fourm