Video series on NOCOPY parameter hint

Finally, finally, FINALLY! I have overcome my resistance to learning Camtasia (or enough of it to not make an utter hash of things). To celebrate my newfound skills, I am releasing today a linked set of videos relating to the NOCOPY parameter hint. Enjoy!

Passing by Reference and Value

In this video, Steven explains the difference between passing a parameter by reference (which happens by default with IN parameters) and passing by value (which happens by default with OUT and IN OUT parameters).

Using NOCOPY to Improve Performance

The NOCOPY parameter hint tells the PL/SQL compiler to pass OUT and IN-OUT parameters "by reference" (meaning: do not copy in, nor copy out). The result is better performance and reduced PGA consumption.

Side-effect of NOCOPY

In this video, Steven demonstrates how use of NOCOPY coupled with an unexpected termination of a subprogram with an unhanded exception can leave your IN OUT actuals partially modified - and not to be trusted!

Using Compile-Time Warnings for NOCOPY

The NOCOPY parameter hint can improve performance of subprograms with OUT and IN OUT parameters. Compile-time warnings help you identify opportunities for NOCOPY.

Comments

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