executeQuery hangs

[Radovan Kobularcik <rk...@atlas.sk>]

Hello,
I have a java swing application comunicating with Derby 10.1.2.6 DB through JDBC.
Since friday one of the application part stoped to work as it cannot get data from database.
I found that the last operation is executeQuery invoked on prepared statement. It stops at this point, no another activity (I'm not absolutely sure there is no exception (90%). App just waits for data from DB endlessly (90%)).

Facts:
- everything works fine when application is launched from windows server (= derby server), problem is when app is invoked from clients (windows net - server & clients)
- all sql queries from DB before failure point work (abount 10 queries) - these queries are invoked in the same way as the problematic one.
- update of database to version 10.2.2.0 and 10.3.2.1 didn't help
- derby trace shows that derby server received sql and there is also "packet" in trace file containing correct return data.
- problematic query (select) is imho big but simple (select from 1 view, it has >800 bytes, size of return data I found in trace file is 27kB)
- derby check_table function returned 1 (ok)

Later on we found that installing application (also with derby db) from scratch to another server and copying old DB files (whole db dir) onto the new server helped.
Doing this with the old server to the original directory didn't help.

What says it is derby problem:
- activity stops at prepStatement.executeQuery()

What says it is Windows net problem:
- app works when launched from server machine, doesn't when launched from clients
- app works when reinstalled to another server
- app doesn't work when reinstalled to original server to the same directory

Now I'm not sure this is problem of derby or application. Could it be problem of Windows? (security, net).
Does anybody have same problem?
What should I check to find where the problem is?

Thank you,
Rado

Re: executeQuery hangs

[Henri van de Scheur <He...@Sun.COM>]

Hi Radovan!

Just a shot in the dark, since I do not know what kind of Windows you 
run. But if it is Vista, is it possible your installation was upgraded 
with SP1 last Friday? In that case your firewall-rules probably have 
changed and you have to grant some permissions one more time. I do not 
see the correlation with your problem, but only because it happened 
'suddenly'.

Henri
Radovan Kobularcik wrote:
> Hello,
> I have a java swing application comunicating with Derby 10.1.2.6 DB through JDBC.
> Since friday one of the application part stoped to work as it cannot get data from database.
> I found that the last operation is executeQuery invoked on prepared statement. It stops at this point, no another activity (I'm not absolutely sure there is no exception (90%). App just waits for data from DB endlessly (90%)).
>
> Facts:
> - everything works fine when application is launched from windows server (= derby server), problem is when app is invoked from clients (windows net - server & clients)
> - all sql queries from DB before failure point work (abount 10 queries) - these queries are invoked in the same way as the problematic one.
> - update of database to version 10.2.2.0 and 10.3.2.1 didn't help
> - derby trace shows that derby server received sql and there is also "packet" in trace file containing correct return data.
> - problematic query (select) is imho big but simple (select from 1 view, it has >800 bytes, size of return data I found in trace file is 27kB)
> - derby check_table function returned 1 (ok)
>
> Later on we found that installing application (also with derby db) from scratch to another server and copying old DB files (whole db dir) onto the new server helped.
> Doing this with the old server to the original directory didn't help.
>
> What says it is derby problem:
> - activity stops at prepStatement.executeQuery()
>
> What says it is Windows net problem:
> - app works when launched from server machine, doesn't when launched from clients
> - app works when reinstalled to another server
> - app doesn't work when reinstalled to original server to the same directory
>
> Now I'm not sure this is problem of derby or application. Could it be problem of Windows? (security, net).
> Does anybody have same problem?
> What should I check to find where the problem is?
>
> Thank you,
> Rado
>
>   


-- 

With regards,



Henri van de Scheur, Database Technology Group,
Sun Microsystems, Trondheim, Norway