Christof Lehmann <[EMAIL PROTECTED]> schrieb am 23.06.05 14:52:34:
> 
> I'm a newbe in working with indices on maxdb. i have a large tables  
> orderlocal with about 200.000 lines (not that large though, isn't it?).
> 
> i create the following indices (order of creating):
> 
> create index ol1 on orderline(bzl1,orderlocal)
> create index ol2 on orderline(bzl2,orderlocal)
> create index ol3 on orderline(bzl1,bzl2,orderlocal)
> 
> i try to analyse the following query:
> 
> explain select * from orderline b where b.bzl1='a' and b.bzl2 = 'b'
> and  
> b.orderlocal in(0)
> 
> Result: STRATEGY EQUAL CONDITION FOR INDEX, Pagecount=2133.
> 
> the analyser says, index ol1 is used. why? doesn't suite index ol3
> much  
> more to the query-statement? How does the optimizer selects the
> indices??

Did you update statistices before you executed "explain"?  If not, that might 
be another explanation.

robert
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