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k_murli_krishnaFlag for India

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DB2 Explain Highlights

1) We have DB2 Express 9.1 on SUSE Linux 10.2.
2) For static parameters, we have no choice but for dynamic paramters, while taking the explain plan, is it better to give static values or just ? which represents average picture. Which plan and cost details are  
accurate?
3) When we are looking for indexing, a more accurate index scan occurs for static/dynamic paramter?
4) db2advis suggests better indexes with ?
5) We can arrive at good effective indexes by understanding cum trial & error. Is there a systematic/mathematical approach to arrive at best indexes or the way db2advis does(but much slower) based upon understanding, query level/internal joins, index structure and mechanism?
6) dynexpln is for dynamic SQL i.e. query using dynamic paramters (in this case is it better than db2expln) OR for queries formed dynamically at run time (in this case what we give as query input - all possibilities 1 at a time?)
7) db2exfmt formats db2expln output. Does this mean both are same? Which is better to use and why?
8) How do Visual Explain, AQT GUI explain plan etc. compare with db2expln, db2exfmt & dynexpln?

Please give point by point answer.
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momi_sabag
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and i think this should be more than 200 points... :-)