Problem - Concatentation for sql --> very bad
Question
- why conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE) instead of conn.createStatement() ?
What happens if you use conn.createStatement()?
Is autocommit off? Does it need to be off?
Is this the type 2 or 4 driver? What happens if you use whichever your not using?
-Tim
Hunter, Sandra wrote:
Okay so just for my own interest (and sanity): here is the place where things are freezing. Can anyone see anything wrong with this?
System.out.println ("ADDRESS"); /* add data to the ADDRESS table */ String addressSQL = "INSERT INTO address (str_address_id, str_mailing, " + "str_street, str_city, str_province, str_postal_code) " + "VALUES " + "(address_seq.currval, '" + parentMailing + "', '" + parentStreet + "', " + "'" + parentCity + "','" + parentProvince + "','" + parentPostalCode + "')";
Statement addressStatement = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
/* execute the statement */ System.out.println ("Address " + addressSQL); //freezing here!! Not every time but always this place //ResultSet addressResults = addressStatement.executeQuery(addressSQL);
boolean addressResults = addressStatement.execute(addressSQL);//still freezes with this one as well
//addressResults.close(); addressStatement.close();
I have several similar lines that all run in sequence, adding data to
different tables. The SQL has been tested in SQL+ and it all works.
This doesn't always freeze. I have beans that I set back to null, and session variables that I do the
same with, at the end of this particular file and at the beginning of the
app.
-----Original Message-----
From: Hunter, Sandra [mailto:[EMAIL PROTECTED] Sent: Thursday, May 29, 2003 11:40 AM
To: 'Tomcat Users List'
Subject: RE: Tomcat STILL freezing - time to look at another app server?
Thanks All! It helps to hear that others have occasionally had this problem. I will look into all your suggestions and see if resolution can be found. Sandra
-----Original Message-----
From: Koes, Derrick [mailto:[EMAIL PROTECTED] Sent: Wednesday, May 28, 2003 12:44 PM
To: 'Tomcat Users List'
Subject: RE: Tomcat STILL freezing - time to look at another app server?
I don't know if this helps any, but this has benefited me.
If using an oracle database, try oracle.jdbc.pool.OracleOCIConnectionPool to get connection pool stats.
-----Original Message-----
From: Carl [mailto:[EMAIL PROTECTED] Sent: Wednesday, May 28, 2003 2:48 PM
To: Tomcat Users List
Subject: Re: Tomcat STILL freezing - time to look at another app server?
I have had a problem that sounds very similar many times (I don't learn very fast.) In all my cases, the problem was running the connection pool out of connections because I wasn't freeing the connections in c couple of places. The fact that it occurs when trying to insert something into the data base indicates that it is related to that activity.
----- Original Message ----- From: "Hunter, Sandra" <[EMAIL PROTECTED]> To: "'Tomcat Users List'" <[EMAIL PROTECTED]> Sent: Wednesday, May 28, 2003 1:48 PM Subject: RE: Tomcat STILL freezing - time to look at another app server?
I am not able to reproduce the problem reliably: that's what is making me crazy. It happens when things are being inserted to the database but never on the same page, never everytime, doesn't matter what else I am doing or what
else
has been done. No one else is accessing this database right now so I am
the
only one and I have tested and retested all the sql. I am stumped. Hopefully running on the server will improve the situation. You know, though, I am demoing the app for my client this afternoon so
maybe
it is just a smelling fear thing. Thanks for the feedback you guys.
-----Original Message----- From: Shapira, Yoav [mailto:[EMAIL PROTECTED] Sent: Wednesday, May 28, 2003 8:35 AM To: Tomcat Users List Subject: RE: Tomcat STILL freezing - time to look at another app server?
Howdy, That's unfortunate ;( I've had tough issues that appeared to be random (like your network traffic hypothesis) and were very difficult to debug ;(
I've tried many many containers / app servers, and always come back to tomcat. This was even before I started contributing to tomcat's codebase, and is more true now than ever.
So you are never able to reproduce the problem reliably?
Yoav Shapira Millennium ChemInformatics
-----Original Message----- From: Hunter, Sandra [mailto:[EMAIL PROTECTED] Sent: Wednesday, May 28, 2003 11:26 AM To: 'Tomcat Users List' Subject: Tomcat STILL freezing - time to look at another app server?
Well this issue continues. Code has been commented, logged, oracle permissions all tickety boo, no locks.
It really is intermittent, and in my opinion seems to be somewhat
related
to network traffic. I talked to one of the tech guys and he seemed to
think I
was nuts.
It never happens at night or on the weekends when I am pretty much the
only
one on the network.
Does that sound possible to any one with more experience than I?
Although we moved it to the live server we had some install problems
there
and so I am still running off my dev machine. It is just a regular P4
with
about 1600mhz and 256 ram. Do you think the freezing will cease when running off the server?
And on the other subject: have any of you tried other app servers out there? Do you have any opinions? Tomcat seems to be the industry standard but
if I
can't resolve this freezing issue I might get some pressure to try some different technology.
-----Original Message----- From: Hunter, Sandra [mailto:[EMAIL PROTECTED] Sent: Friday, May 16, 2003 2:52 PM To: 'Tomcat Users List' Subject: RE: Tomcat Freezing?
The lock may be an issue: I'll run that past our DBA but that's the
only
thing I haven't looked at. We have actually moved the app to another machine to see if that makes
any
difference. If anyone gets a bright idea I would love to hear it! Puzzled Sandra
-----Original Message----- From: Jason Bainbridge [mailto:[EMAIL PROTECTED] Sent: Friday, May 16, 2003 12:11 PM To: Tomcat Users List Subject: Re: Tomcat Freezing?
I'm running out of ideas myself... I gather this is quite a beefy
machine
you're running it on?
Are you using the right version of the Oracle Thin Driver for the
version
of
Oracle you are running? Have you got a DBA on site or are you able to
look
at the appropriate v$ view to see what query it died on and possibly why?
It's not something like not releasing a lock on a record or commits not being on or something silly like that in the Oracle config?
Jason
On Sat, 17 May 2003 02:29 am, Hunter, Sandra wrote:
I spoke too soon. I am really stumped now. Code that ran yesterday, won't run today. I have gone through it line
by
line, commenting it all out, and then gradually adding in each line,
and
then it runs again. Same code. No changes. If I restart Tomcat the code will run. Sometimes. Other times not. I have looked at the Tomcat logs and I don't see anything that tells
me
anything. There must be some common event that is causing this but I can't seem
to
place it or find it. It almost seems like the code needs a warm up run before it can
really
get
going. How weird is that? Any idea what I should be looking for? Besides a psychiatrist? Sandra
-----Original Message----- From: Hunter, Sandra [mailto:[EMAIL PROTECTED] Sent: Thursday, May 15, 2003 3:29 PM To: 'Tomcat Users List' Subject: RE: Tomcat Freezing?
Well it has stopped. I think I did have a code error: I was calling
the
wrong statement for a resultset, so calling it twice. I have made
such an
error before without causing such a crisis but I guess Tomcat had
just
had
enough of my foolishness. It is so frustrating to not know why something is happening and I
thought
I
had done everything right but after doing it twice it got sorted out. Thanks all! Sandra
-----Original Message----- From: Jason Bainbridge [mailto:[EMAIL PROTECTED] Sent: Thursday, May 15, 2003 2:41 PM To: Tomcat Users List Subject: Re: Tomcat Freezing?
I assume you are using the Oracle JDBC Thin drivers then? Just want
to
make
sure you aren't doing anything like using the JDBC-ODBC bridge but I
doubt
it just clutching at straws...
Do the log files shine any info on the problem? (not your log
messages
but
the Tomcat logs)?
J.
On Fri, 16 May 2003 05:28 am, Hunter, Sandra wrote:
The queries all run in Oracle. Other pages with SQL queries all run fine. The privileges all allow for the SQL stuff I am doing which is very basic. I am going through the commenting process again and lines
that
ran
fine half an hour ago with no changes made now seem to be stalling. Even when I close the app, Tomcat is still hung and I can't close
it
from
the command line. I close all my resultsets and statements and connections. I could include all my code but there are thousands of lines and
there
seems to be no consistent line or lines that are causing the
problem.
-----Original Message----- From: George Sexton [mailto:[EMAIL PROTECTED] Sent: Thursday, May 15, 2003 2:10 PM To: Tomcat Users List Subject: RE: Tomcat Freezing?
Have you looked at your database and made sure that you don't have
blocking
issues keeping your queries from running?
-----Original Message----- From: Hunter, Sandra [mailto:[EMAIL PROTECTED] Sent: Thursday, May 15, 2003 3:06 PM To: 'Tomcat Users List' Subject: RE: Tomcat Freezing?
This freezing problem seems to be really intermittent. I am really
stumped.
I have put in printlines every other line and commented out just
about
everything and then gradually added stuff and it will freeze at
pretty
(apparently) random places. It stopped doing it with one page (for
no
apparent reason) and now has started doing it with another. But it doesn't happen consistently. No applets, etc. Nothing fancy at all just straight ahead java and
sql.
I surely am confused.
-----Original Message----- From: Bill Barker [mailto:[EMAIL PROTECTED] Sent: Wednesday, May 14, 2003 10:40 PM To: [EMAIL PROTECTED] Subject: Re: Tomcat Freezing?
I second Matt's suggestions. If you are really stumped as to the problem, try inserting logging statements every few lines in your
JSP
(if
you are not using a real logging package, such as log4j, Tomcat's
default
JSPPage class extends GenericServlet, so you can simply do
something
like
<% log("Getting DB info"); %>).
"Matt Wiseley" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] Sandra,
If it's only happening with one JSP, and it happens every time it's requested, it's almost certainly a coding problem. Without looking
at
the
source code, it's pretty hard to say what's causing it. From my own experience, I have seen only two coding errors that "hang" Tomcat.
The
first is opening database connections from a pool and not closing
them.
The
second is a page that forwards to itself somehow. Also look for
code
that
creates an endless loop of some kind, although these usually either
run
out
of memory, cause an overflow, or time out.
Matt
Being new and inexperienced as I am I don't know how to problem
solve
this issue.
I have a jsp app that I am running in Tomcat 4.0 with Apache 2
HTTP
server
on a Win2k pro box.
My apologies to those who receive this twice. Some weirdness with
my
address
book.
All has been well until now. I have one page that is freezing: it
doesn't
complete loading after several minutes. When I try to shut down
Tomcat
it
also doesn't do anything. It displays this message in the command
line:
"Stopping service Tomcat-Standalone" but after several minutes
the
window
is
still open and the task manager tells me Tomcat is still running.
I
have tried stopping tomcat,deleting all the files in the work
folder
and restarting Tomcat.
I know it must be something to do with the page, but I don't know
where
to begin to look or what to look for.
Any ideas?
Sandra Patricia Hunter
---------------------------------------------------------------------
To unsubscribe, e-mail:
[EMAIL PROTECTED]
For additional commands, e-mail:
[EMAIL PROTECTED]
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail:
[EMAIL PROTECTED]
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail:
[EMAIL PROTECTED]
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail:
[EMAIL PROTECTED]
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail:
[EMAIL PROTECTED]
-- Jason Bainbridge KDE Web Team - http://kde.org [EMAIL PROTECTED]
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential,
proprietary
and/or privileged. This e-mail is intended only for the individual(s) to whom it is addressed, and may not be saved, copied, printed, disclosed or used by anyone else. If you are not the(an) intended recipient, please immediately delete this e-mail from your computer system and notify the sender. Thank you.
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] This electronic transmission is strictly confidential to Smith & Nephew and intended solely for the addressee. It may contain information which is covered by legal, professional or other privilege. If you are not the intended addressee, or someone authorized by the intended addressee to receive transmissions on behalf of the addressee, you must not retain, disclose in any form, copy or take any action in reliance on this transmission. If you have received this transmission in error, please notify the sender as soon as possible and destroy this message.
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
