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Tracing Errors


For most of us, writing procedures, functions or say just a PL/SQL Code Block based on a given logic is wasy. The challenge lies in designing and placing the "Exception Handling" Block with the intent of capturing the correct line of Code that raised the exception so that one can them Zoom into the erroneous line and do make the necessary fixes. Now many of you would agree that this comes with experience 'n' ofcourse proactive thinking.
Now conder the following Code Snippet,

WHEN NO_DATA_FOUND
THEN dbms_output.put_line (sqlerrm);
END;

Looks familiar...? But here's a catch - this code block will keep rescuing us as far as Error String is less than 255 Characters. (The limitation with put_line() is that it can capture a max of 255 Characters).
Oracle has revolved this by its offering -DBMS_UTILITY.FORMAT_ERROR_STACK

BEGIN
error();
EXCEPTION WHEN OTHERS THEN
DBMS_OUTPUT.PUT_LINE( SQLERRM );
DBMS_OUTPUT.PUT_LINE( DBMS_UTILITY.FORMAT_ERROR_BACKTRACE );
END;
/
ORA-00900: invalid SQL statement
ORA-06512: at line 2

Now, as evident from output above, the information provided in error stack is sufficent for application error logs and can be worked upon accordingly. And the best part is there's no limitation of number of characters we can capture in error stack. Makes life easy indeed :)

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Intereseting --- 249 days bug for Oracle on Linux servers

--contributed by Manjunath Ulthi, Senior DBA at Infosys Technologies limited

1 Introduction

Problem: OCI client spins when machine uptime >= 249 days in Linux machines. Once the uptime crosses 249 days the database client hangs and leads to high CPU utilization and server hung state. The user will not be able to connect to the databases This is oracle known bug 4612267.


Solution: This can be handled by applying the patch 4612267.


The patch has been applied in the servers server126, server041 & server120 and tested. After the patch has been applied the client connections were normal after 249 days and all the operations of databases/applications were normal and didn’t encounter any problems.

For further information refer the Metalink Notes

Note: 338461.1: SQL*Plus With Instant Client 10.2.0.1 Hangs, When System Uptime Is More Than 248 Days

Note:4612267.8 : Bug 4612267 - OCI client spins when machine uptime >= 249 days

2 General Instructions

Procedure to apply the patch

1. Download the …