Hello all. Several days ago we saw some strange behavior with an Oracle 
database after the restart of a tomcat webapp. Immediately after restart, 
Oracle was processing the query for a certain page using an improper index that 
caused the page/query to hang. We've taken a look at the configuration for our 
CBO and come to the conclusion that Oracle should not have reparsed the query 
unless the query were somehow different, but we can't find anything to indicate 
the query changed.

While it's possible there's something we missed, I would like to know if anyone 
out there knows why a webapp restart would cause the database to reparse and 
choose a new execution plan. We're running Tomcat 5.5.12 with JDK 1.5.0_12. 
This is on an RHEL4 server running a 2.6.9 kernel. The tomcat instance is using 
a JDBC thin client to connect to the database. I know of no queries that are 
made to the database immediately upon startup, and it's certainly not this one 
since the query is page specific.

Can anyone point out any instances they've had where Tomcat or Tomcat with the 
Oracle JDBC driver has exhibited similar behavior?

Many thanks in advance,

Dan

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