I have a pretty complicated query containing several columns generted
via olap windowing expressions. This query without any 'filtering'
where clauses would run in about 3-4 minutes. However the moment I add
a simple filtering clause like column_a = 20, the query would finish
in less than a second (due to different access plans)
i.e

select <lotsofcolumns>
from <lotsofjoins>
where <severaljoinconditions>
will finish in 4 mins.

select <lotsofcolumns>
from <lotsofjoins>
where <severaljoinconditions>
         and column_a = 20   -- < Extra filter
will finish in < 1 sec.

My problem is I cannot put the extra filter in the query as it has to
sit behind a view which would add the required filters as needed

ie. create view view1 as (select <lotsofcolumns>
from <lotsofjoins>
where <severaljoinconditions>
);

select *
from view1
where column_a = 25
still takes 4 mins.

Is there a way to incorporate the additional clauses everytime the
view is run, i.e. somehow always re-compile the view at runtime taking
into account the additional clauses.

This is on DB2 9.1 FP2 on AIX

Thanks in advance for your help!