java connection

[TheDash]

Hi,

Can a java application use connection pooling to connect to oracle? One of the applications is trying to get a connection to the database and it is erring out. Stack is

at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:134)
at oracle.jdbc.ttc7.TTIoer.processError(TTIoer.java:289)
at oracle.jdbc.ttc7.O3log.receive1st(O3log.java:407)
at oracle.jdbc.ttc7.TTC7Protocol.logon TTC7Protocol.java:260)
at oracle.jdbc.driver.OracleConnection.<init>(OracleConnection.java:360)
at oracle.jdbc.driver.OracleDriver.getConnectionInstance(OracleDriver.java:521)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:325)
at java.sql.DriverManager.getConnection(DriverManager.java:512)
at java.sql.DriverManager.getConnection(DriverManager.java:141)
at oracle.jdbc.pool.OracleDataSource.getConnection(OracleDataSource.java:171)
at oracle.jdbc.pool.OracleConnectionPoolDataSource.getPhysicalConnection(OracleConnectionPoolDataSource.java:149)
at oracle.jdbc.pool.OracleConnectionPoolDataSource.getPooledConnection(OracleConnectionPoolDataSource.java:95)
at oracle.jdbc.pool.OracleConnectionPoolDataSource.getPooledConnection(OracleConnectionPoolDataSource.java:63)
at oracle.jdbc.pool.OracleConnectionCacheImpl.getNewPoolOrXAConnection(OracleConnectionCacheImpl.java:547)
at oracle.jdbc.pool.OracleConnectionCacheImpl.getPooledConnection(OracleConnectionCacheImpl.java:404)
at oracle.jdbc.pool.OracleConnectionCacheImpl.getConnection(OracleConnectionCacheImpl.java:298)
at oracle.jdbc.pool.OracleConnectionCacheImpl.getConnection(OracleConnectionCacheImpl.java:268)
at com.bbb.app.getDBConnection(Service.java:1074)
at com.bbb.app.getDBConnection(Service.java:1054)
at com.bbb.app.reportError(Service.java:3636)
at com.bbb.app.query.getResponse(query.java:424)
at com.bbb.app.query.run(query.java:67)

I know of applications that usually use jdbc. I don't think it runs in an appserver. How is it using connection pooling? Please explain in detail. Thank you

 

[sedj]

thats not the whole stack trace is it ?!!

--------------------------------------------------
Free Database Connection Pooling Software

http://www.primrose.org.uk

 

[TheDash]

Hi,

it is the whole stack trace. There is one last (bottom) line that I forgot to put, it is

at java.lang.Thread.run(Unknown Source)

 

[sedj]

No, there is another line or two at the top ... I've never seen a stack dump beginning "at bla.bla.bla." ... such as :

NullPointerException caused by :
SomeClass.line (a line)
at ...

--------------------------------------------------
Free Database Connection Pooling Software

http://www.primrose.org.uk

 

[TheDash]

Hi,

it actually starts with

java.sql.SQLException: ORA-00020: maximum number of processes (215) exceeded

 

[sedj]

Well there you go.

You have blown the db stack of processes (connections). I expect you are either :
a) not closing connections
b) not closing statements

(Leaving cursors open would result in a ORA error "maximum cursors/sessions exceeded").

--------------------------------------------------
Free Database Connection Pooling Software

http://www.primrose.org.uk

 

[TheDash]

Thanks a lot,

Could you clarify these

Is it because of a program bug?
(not closing statements, connections -- is it clear from this stack trace?) OR

Is it because, some other applications/application servers are using connection pooling and they are competing for connections with this program?

If the first is true, what is the best way to debug the program? Please suggest

 

[sedj]

I expect you are either :
a) not closing connections
b) not closing statements

--------------------------------------------------
Free Database Connection Pooling Software

http://www.primrose.org.uk

 

[sedj]

>>>>> If the first is true, what is the best way to debug the program? Please suggest

I can assure you it is NOT a fault of connection pooling.
The best way you can debug it is CLOSE YOUR CONNECTIONS !!!

--------------------------------------------------
Free Database Connection Pooling Software

http://www.primrose.org.uk

 

[sedj]

Incidentally, if you were using primrose as your connection pooling software, it would tell you the exact code & line that was leaving connections open !!!

--------------------------------------------------
Free Database Connection Pooling Software

http://www.primrose.org.uk

 

[TheDash]

HI, Can a JDBC thin driver perform connection pooling?