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Home -> Community -> Usenet -> c.d.o.misc -> Oracle hangs on select statement on certain computers
I'm not really sure where to post this as I'm not really sure where the
problem lies, but I THINK it may be an oracle problem:
I have a problem with certain select statements hanging (either
retrieving several hundred rows than just stopping on the same row
every time, or just hanging before retrieving anything.) These exact
statements do work on most of our computers and up until a few weeks
ago ran fine on the few that now hang. And even on the computers that
have the problem, it's only 3 particular databases (2 of which are on
the same server but all of which belong to the same client and are
accessed via VPN.) This problem is consistantly reproducable on the
same computers with the same statements with the same databases. The
statements are being run through an application that we created in
PowerBuilder and I have also tried them in a database utility that we
also created in PowerBuilder, SQL Plus, & TOAD for Oracle. On the
computers that have the problem, the statements freeze in both our
PowerBuilder apps, and in a version of TOAD (I forget what) prior to
8.6.0.38; they work in SQL Plus (which I'm told DOESN'T use the oracle
API) and TOAD 8.6.0.38. We have recently upgraded TOAD on all machines
which is why I'm not sure what the version was that was failing, but in
the previous version the statements DID return fine when run as single
statements (which retrieves a few rows into a table and retrieves the
rest when you scroll down); they just hung when executing as a script
(which retrieves everything at once.)
Not everyone has the exact same versions of everything (particularly
Oracle and Windows-we all use XP Pro but there still are version
differences..) or the exact same programs installed. I have tried two
computers with the same Oracle version though and one worked while one
did not. One strange thing about this problem is that the 3 computers
that have the problem (there are 3 that I know of and they all started
having the problem a few weeks ago) are the 3 that access the
particular databases the most; this may or may not be coincidence. As
I mentioned, the databases are accessed by us over VPN but the client
(who accesses them directly) reported to us the other day a problem
that they had in which it hangs when the app runs certain insert or
delete statements. We are aware that locks on the tables could cause
these problems but we tried and the client tried when everything was
unlocked and they hung, locking the tables, on all their databases
while only two of the three hung for us.
All three of their servers are at oracle 9.2.0.6.0; I just now thought of asking if this upgrade was made recently; if so, I'll post that info in here tomorrow.
Oh, and by the way, not only does the structure (ie. columns/tables/etc used) affect which statements hang, but the data used in them (ie. "where flag='x'" vs. "where flag=' '"), which doesn't change the execution plan, is a factor.
So does anyone have any suggestions?
Thanks, Dan Received on Mon Feb 20 2006 - 16:35:12 CST