Is there an option in Oracle SQL Developer (I use version 4.1.5) to make it reconnect to the DB when needed?
For example, if I start an SQL script but the DB was disconnected, then it should reconnect with minimum hassle and execute the script instead of giving a SQL Error: Closed Connection message.
Note: I'm not interested in keep-alive (what most related questions discuss). If I don't use it today, then it is OK to disconnect. I just want it to reconnect next time I use it.
No.
Auto-connecting dropped connections sounds good in theory, but the 'auto' part is where the trouble begins.
I have a standing ER to add the reconnect button to the dropped connection ERROR message.
In at least SQL Developer version 20.2 this is implemented:
when running an SQL operation when the DB was disconnected after a while, the connection is restored and the operation is executed (there is also a dialog shown telling about the fact).
Related
I am new to Oracle database in general, but I'm attempting to get Oracle's SQL Developer running on a workstation that has pre-configured System DSNs created for an OracleRDB database. I've confirmed the ODBC connections are working because I can use MS Access to connect and link to the tables. The "test" options within ODBC also succeed. Now I am trying to get a similar connection created using SQL Developer so I can see the column types and write queries in a more useful editor.
Here's what I have available when examining the ODBC connection properties:
Now I'm trying to create a duplicate connection in SQL Developer, but I'm at a loss for why things don't work. I first tried using the default SQL Developer installation, but couldn't get things working. Then I discovered there's an OracleRDB extension available, so I installed that, but I keep getting this error when attempting to use similar values:
As I stated, these ODBC connections were pre-configured on the workstation I'm using, so I don't know anything more than what is provided by the Oracle ODBC driver window.
Is there something obvious I'm not seeing or doing to replicate this connection in SQL Developer? Or perhaps something else I can do to debug this to learn more?
UPDATE
On the advice of one answer I'm trying to make the connection with JDBC, but having a hard time understanding what I'm doing wrong. Here's another screenshot with the connection parameters I have available, but with the server and database names changed:
With these values (the port came from my tnsnames.ora file), if I try to make a JDBC connection I keep getting the following error from SQL Developer:
One final attempt I did was to use the proper values in the Oracle RDB tab, and when I use them and click 'test' the Testing Connection dialog just spins and never seems to return:
So I apologize for the long post here, but I'm struggling because there's just something I am really not understanding about how this all works. I appreciate everyone who took the time to read this question.
Oracle SQL Developer is a Java Application. You'll need to get the JDBC Driver for RDB.
Once you have that, in the SQL Developer preferences, find the Third Party JDBC section, and then use that to add an entry and point to the JAR for what you just installed.
Step by step instructions here.
Working connection string for RDB Thin Driver:
RDB_DB_CONN_STR = "jdbc:rdbThin://node.myplace.com:1707/";
where node.myplace.com is the name of the OpenVMS node hosting the RDB Thin Driver, 1707 is the port number assigned to the RDB Thin Driver.
I am using sqlplus to connect to an 10g server and execute an anonymous block which takes a while to run. For some reason my connection is consistently dropped. Is there anything I should check in the Oracle configuration that might cause this to happen?
I'm not sure how to reference another question with SO, but here's another viable scenario...
Settings of connection timeout for Oracle database
I'm currently troubleshooting a VB6 application that sporadically comes up with the following error:
[Oracle][ODBC][Ora]ORA-01013: user requested cancel of current operation
All of the research I've done on this error states that it is either an actual request for cancellation by the user or a timeout. It can't be a request for cancellation because the input is coming in from an automated source, so it must be a timeout. One thing I read online was to un-check the query timeout checkbox in the DSN configuration box but my program uses a DSN-less connection to the database, which is an Oracle 10g database.
There are several queries in this program but it always fails on one query in particular, however I can't reproduce the error in a test environment using all of the same input to the program that caused the error in the first place.
A co-worker of mine suggested doing a rollback after each query even though the queries are read only because some kind of buffer might be getting filled up or something of the like, but this didn't work. At this point I don't even know how to continue troubleshooting it because I can't reproduce the error. If someone could give me any idea of what is going on and how to fix the problem I'd greatly appreciate it. Thanks in advance!
All of the options that you can choose when setting up a DSN can be specified in the connection string if you are using a DSN-less connection. If you want to disable query timeouts, you would add
QTO=F
to the connection string. So your new connection string would be something like
DRIVER={Oracle ODBC Driver};UID=Kotzwinkle;PWD=whatever;DBQ=instl_alias;QTO=F;
Do you know any reason to get the following error when I'm taking a few Oracle Reports?
"FRM-40735: ON-ERROR trigger raised unhandled exception ORA-03114"
This happens some times to a few users.
ORA-03114: not connected to ORACLE is an error with several possible causes. As it suggests, it means your client (Forms in this case) has been disconnected from the database.
It's possible that the database or the listener has shut down. Or perhaps a problem with the client has caused the database to disconnect you. There may well be some messages in the database alert log.
ORA-03114 is "Not Connected to Oracle" - i would begin by troubleshooting this issues first.
Either you got disconnect in some way (perhaps an idle connection timeout)
or someone shut down the DB while you were connected. Either way, it means you are disconnected from the database.
I've got a load-balanced (not using Session state) ASP.Net 2.0 app on IIS5 running back to a single Oracle 10g server, using version 10.1.0.301 of the ODAC/ODP.Net drivers. After a long period of inactivity (a few hours), the application, seemingly randomly, will throw an Oracle exception:
Exception: ORA-03113: end-of-file on communication channel at
Oracle.DataAccess.Client.OracleException.HandleErrorHelper(Int32
errCode, OracleConnection conn, IntPtr opsErrCtx, OpoSqlValCtx*
pOpoSqlValCtx, Object src, String procedure) at
Oracle.DataAccess.Client.OracleCommand.ExecuteReader(Boolean requery,
Boolean fillRequest, CommandBehavior behavior) at
Oracle.DataAccess.Client.OracleCommand.System.Data.IDbCommand.ExecuteReader()
...Oracle portion of the stack ends here...
We are creating new connections on every request, have the open & close wrapped in a try/catch/finally to ensure proper connection closure, and the whole thing is wrapped in a using (OracleConnection yadayada) {...} block. This problem does not appear linked to the restart of the ASP.Net application after being spun down for inactivity.
We have yet to reproduce the problem ourselves. Thoughts, prayers, help?
More: Checked with IT, the firewall isn't set to kill connections between those servers.
ORA-03113: end-of-file on communication channel
Is the database letting you know that the network connection is no more. This could be because:
A network issue - faulty connection, or firewall issue
The server process on the database that is servicing you died unexpectedly.
For 1) (firewall) search tahiti.oracle.com for SQLNET.EXPIRE_TIME. This is a sqlnet.ora parameter that will regularly send a network packet at a configurable interval ie: setting this will make the firewall believe that the connection is live.
For 1) (network) speak to your network admin (connection could be unreliable)
For 2) Check the alert.log for errors. If the server process failed there will be an error message. Also a trace file will have been written to enable support to identify the issue. The error message will reference the trace file.
Support issues can be raised at metalink.oracle.com with a suitable Customer Service Identifier (CSI)
Add Validate Connection=true to your connection string.
Look at this blog to find more about.
DETAILS:
After OracleConnection.Close() the real database connection does not terminate. The connection object is put back in connection pool. The use of connection pool is implicit by ODP.NET. If you create a new connection you get one of the pool. If this connection is "yet open" the OracleConnection.Open() method does not really creates a new connection. If the real connection is broken (for any reason) you get a failure on first select, update, insert or delete.
With Validate Connection the real connection is validated in Open() method.
Check that there isn't a firewall that is ending the connection after certain period of time (this was the cause of a similar problem we had)
end-of-file on communication channel:
One of the course of this error is due to database fail to write the log when its in the stage of opening;
Solution check the database if its running in ARCHIVELOG or NOARCHIVELOG
to check use
select log_mode from v$database;
if its on ARCHIVELOG try to change into NOARCHIVELOG
by using sqlplus
startup mount
alter database noarchivelog;
alter database open;
if it works for this
Then you can adjust your flashrecovery area its possibly that your flashrecovery area is full
-> then after confirm that your flashrecovery area has the space you can alter your database into the ARCHIVELOG
This error message can be thrown in the application logs when the actual issue is that the oracle database server ran out of space.
After correcting the space issue, this particular error message disappeared.
You could try this registry hack:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters]
"DeadGWDetectDefault"=dword:00000001
"KeepAliveTime"=dword:00120000
If it works, just keep increasing the KeepAliveTime. It is currently set for 2 minutes.
The article previously mentioned is good. http://forums.oracle.com/forums/thread.jspa?threadID=191750 (as far as it goes)
If this is not something that runs frequently (don't do it on your home page), you can turn off connection pooling.
There is one other "gotcha" that is not mentioned in the article. If the first thing you try to do with the connection is call a stored procedure, ODP will HANG!!!! You will not get back an error condition to manage, just a full bore HANG! The only way to fix it is to turn OFF connection pooling. Once we did that, all issues went away.
Pooling is good in some situations, but at the cost of increased complexity around the first statement of every connection.
If the error handling approach is so good, why don't they make it an option for ODP to handle it for us????
//First start the database in mount mode
startup mount
//Disable archivelog
alter database noarchivelog
//Then put db in open
alter database open