Is my PL/SQL code going to perform better? I have rewritten my Oracle code. Now, how do I tell if my coding approach A is better than coding approach B? If someone were to ask you the above question, typically, you would give the following answers If one approach is faster than the other, that … Continue reading Oracle PL/SQL – Quantify Code Performance For Comparison Of Different Approaches – Tom Kyte’s “runstats”
Commit or rollback a SELECT, really? Occasionally, you would be working with your favorite Oracle tool and when you are ready to close the tool, it will prompt you to either commit or rollback your work. “What work?”, you wonder. The problem is, you have only done SELECT’s. Why is it prompting you to commit … Continue reading Oracle – Why Is Toad Asking Me To Commit/Rollback A SELECT With No Transaction?
What is a Semaphore? Instead of a clinical illustration of exclusive row lock and exclusive table lock usage in Oracle, here we will try to use them to highlight a higher level concept – Implement a semaphore mechanism. Wikipedia defines semaphore as below: In computer science, a semaphore is a variable or abstract data type … Continue reading Oracle – PL/SQL – Using ROW/TABLE Locks To Implement Application/Job Semaphore To Handle Race Conditions
Numbers and meaning it comes to numbers, the easiest way to get a point across to majority of the people is to express something in terms of percentage. Let us consider an example where a query produces the “waits” Oracle experienced overall in terms of “Number of waits” and the “Time waited”. This produces: WAIT_CLASS … Continue reading Oracle System & Session Wait Big Picture Analysis- Using RATIO_TO_REPORT Function
The v$session view If you do not know already, to check who is connected and since when, what their connection status is etc., you would use dynamic view v$session. The view has the following columns: You would kill the required session by issuing Note: The IMMEDIATE option of the above command just returns control … Continue reading Oracle – My KILL’ed Session Continues To Stay On In KILLED Status, Why?