Hi Phil,

Sorry to bring this topic up.
This is the exact issue we are having currently. The error messages is
very similar.
We are running 2 connection pools in 2 different app server connecting
to 1 FB.

Appreciate if you could post your notes on this if possible (since it's
already >3 years old =) )

Thanks,
John

--- In Firebird-Java@yahoogroups.com, "phil_hhn" <time_lord@...> wrote:
>
> (This call being raised as suggested by Roman in the main FB support
> NG...)
>
> We had some multi-threaded code running where both threads were using
> the same JDBC connection; if they ran SQL code at the same time,
> errors could occur. (The threads have since been changed to have their
> own JDBC connections.)
> Sometimes the error was a NullPointerException, or in some cases "GDS
> Exception. 335544332. invalid transaction handle (expecting explicit
> transaction start)".
>
> I created a test case to mimic the situation but could not reproduce
> the error (so no sample code, sorry). However I have captured some of
> the stack traces (from our main application), as below. (Sometimes I'd
> have to run the code several times before the timing of the threads
> clashed and an error would occur.)
> We are using Firebird 1.5.3 (4870), JDBC driver 2.1.1.
>
> Most common error:
> =================================
> org.firebirdsql.jdbc.FBSQLException: GDS Exception. 335544332. invalid
> transaction handle (expecting explicit transaction start)
> at
> org.firebirdsql.jdbc.AbstractStatement.executeQuery(AbstractStatement.java:228)
> << Our code, running a query >>
>
>
> More worrying is this one:
> =================================
> java.lang.NullPointerException
> at
> org.firebirdsql.gds.impl.wire.AbstractJavaGDSImpl.iscDsqlExecute2(AbstractJavaGDSImpl.java:1119)
> at
> org.firebirdsql.gds.impl.GDSHelper.executeStatement(GDSHelper.java:224)
> at
> org.firebirdsql.jdbc.AbstractStatement.internalExecute(AbstractStatement.java:1109)
> at
> org.firebirdsql.jdbc.AbstractStatement.executeQuery(AbstractStatement.java:219)
> << Our code, running a query >>
>
> Followed immediately by:
> =================================
> org.firebirdsql.jdbc.FBSQLException: GDS Exception. 335544726. Error
> reading data from the connection.
> null
> Reason: Error reading data from the connection.
> null
> at
> org.firebirdsql.jdbc.InternalTransactionCoordinator$LocalTransactionCoordinator.ensureTransaction(InternalTransactionCoordinator.java:313)
> at
> org.firebirdsql.jdbc.InternalTransactionCoordinator$LocalTransactionCoordinator.executionStarted(InternalTransactionCoordinator.java:342)
> at
> org.firebirdsql.jdbc.InternalTransactionCoordinator.executionStarted(InternalTransactionCoordinator.java:38)
> at
> org.firebirdsql.jdbc.AbstractStatement.notifyStatementStarted(AbstractStatement.java:243)
> at
> org.firebirdsql.jdbc.AbstractStatement.notifyStatementStarted(AbstractStatement.java:234)
> at
> org.firebirdsql.jdbc.AbstractStatement.executeQuery(AbstractStatement.java:216)
>
> ... all subsequent queries resulted in the following (obviously
> Firebird had crashed, and I verified this by checking the windows
> event log which had an entry for "fbserver.exe: terminated abnormally"):
> =================================
> org.firebirdsql.jdbc.FBSQLException: GDS Exception. 335544721. Unable
> to complete network request to host "".
> Reason: Unable to complete network request to host "".
> at
> org.firebirdsql.jdbc.InternalTransactionCoordinator$LocalTransactionCoordinator.ensureTransaction(InternalTransactionCoordinator.java:313)
> at
> org.firebirdsql.jdbc.InternalTransactionCoordinator$LocalTransactionCoordinator.executionStarted(InternalTransactionCoordinator.java:342)
> at
> org.firebirdsql.jdbc.InternalTransactionCoordinator.executionStarted(InternalTransactionCoordinator.java:38)
> at
> org.firebirdsql.jdbc.AbstractStatement.notifyStatementStarted(AbstractStatement.java:243)
> at
> org.firebirdsql.jdbc.AbstractStatement.notifyStatementStarted(AbstractStatement.java:234)
> at
> org.firebirdsql.jdbc.AbstractStatement.executeQuery(AbstractStatement.java:216)
> << Our code, running a query >>
>
>
> Hope this helps. Let me know if you want any other details.
> Thanks, Phil
>