hi all
when i am running a query against a database i am getting the following error

SQL0437W performance of this complex query may be sub-optimal.reason code:"3". SQLSTATE=01602
0 row(S) affected.

i am running this on db2V8.7 on solaris.

this a big query with lot of predicates and joining around 9 tables.

i have tried running runstats on tables invoved in the query but still the problem is not fixed.
ibm explains this reason code as optimizer cost underflow. what exactly this means and how to solve this problem.
actually this query was running fine earlier.

Thanks.......

It is a warning message. Do you have a problem with the answer set or the query execution time?

Hi,
if there are performance problems this means two thinks:
1. SQL is badly written -> rewrite SQL.
2. SQL is really too complex -> make it more simple.

Can you post the SQL and table definitions including primary and foreign keys?
Hope this helps,
Grofaty