Hi all,
I'm experiencing following problem and would like to know if someone else also hit this one before and has a suggestion how to solve it:
I have a pretty complicated SELECT statement that per definition returns only a few rows (~30). With no further optimization it takes ~20 seconds to return the full dataset in Oracle SQL Developer. If you add the */+ PUSH_PRED(name_of_some_inner_view) /* hint (hint is correct, stars got eaten by the OTN-forum syntax), the statement takes less than 0.5s to execute (still in SQL Developer). I saved the statement
with the hint as VIEW. Selecting from the VIEW in SQL Developer is also fast.
Now if I call the statement from JDBC (Tomcat webapp), I can see from the server console that the statement is 1:1 100% the same as the one I execute in SQL Developer. Nevertheless it takes about 20 seconds to complete.
Here my details:
SELECT banner FROM v$version;
BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Express Edition Release 11.2.0.2.0 - Production
PL/SQL Release 11.2.0.2.0 - Production
CORE 11.2.0.2.0 Production
TNS for 32-bit Windows: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production
JDBC Driver used: some old odbc14.jar as well as current odbc6.jar for 11.2.0.2.0 from http://www.oracle.com/technetwork/da...10-090769.html
SQL Developer: current version 3.2.20.09
From my reading this could go wrong:
- JDBC doesn't know the VIEW's column data types and Oracle behaves mysterious because of this (=there must be more to the SELECT than just the string, some meta-information)
- For some reason the hint
inside the VIEW is not used (unlikely)
I also tried a Table Function/Pipelined table and selected from it as a workaround, but the result is the same: Selecting from Function is fast from SQL Developer, but slow from JDBC. All other statements that come from JDBC are as fast as they should be. I really don't know what to think of this and where the error might be.
Is there some setting that tells Oracle not to use hints when called from JDBC?
Thank you & Best regards,
Blama