Some insight on Oracle Exception Handling

Like some high level programming language oracle provide some pretty feature on exception handling. Like other high level language here you can catch specific exception and handle that accordingly. Here you can also create your own exception also.

Firstly, how to catch specific exception :-

Suppose for network problem one of your dblink face problem and generate Oracle Exception ORA-3135. To catch this exception, you should define an exception with this exception number and then use the given name to catch this exception. That is create an exception using following code -

connection_lost Exception;
PRAGMA EXCEPTION_INIT(connection_lost, -3135);

Then in Exception block write the following -

when connection_lost then
/*some statements*/

Secondly, create and raise custom error:

create custom exception by following command -
cust_exception Exception;
PRAGMA EXCEPTION_INIT(cust_exception, -20001);

then command to raise this exception -
RAISE cust_exception;

Then catching this exception is same as other exception. There is an overload of RAISE_application_error which takes a third bool parameter. This parameter determines whether they data will be put on empty stack or top of stack.

Thirdly, Log Exception from the stack:

To get maximum log of exception, call DBMS_UTILITY.FORMAT_ERROR_STACK function and log the output. It will give not only top of stack but also all content of the procedure error stack. Along with this use DBMS_UTILITY.FORMAT_ERROR_BACKTRACE to log line from which error is generated. It is available from Oracle 10g.

For more information visit following links -

http://download.oracle.com/docs/cd/B19306_01/appdev.102/b14261/errors.htm

http://www.oracle-developer.net/display.php?id=318

Console/admin log in Windows server

Sometimes when you want to log in a windows server OS you may get an error like terminal exceeded maximum number of user. But you have to do some admin work on the windows server; suppose disconnecting one of this user, then what you have to do?

just open command prompt, execute remote desktop connection with the following command-

mstsc -v:IP_OF_SERVER /F -admin

Then give your user & password. This is so simple!!

One thing keep in mind every time, that is when exiting the server always use log off. If you do not log off then if disconnect create some problem (which I face several time) then you cannot log in again as admin/console.