Re: [Fwd: performance: view or function?]

[Robert Treat <robert(at)omniti(dot)com>]

On Thursday 08 May 2008 06:16:06 Julius Tuskenis wrote:
> Hello,
>
> I have one question - what is the difference between the view and a
> function returning a data set? I mean the performance. Which is better
> to use? If its the same, I would use functions, because I could use
> other languages not just SQL to get the results I want.
>

If the sql you need to run is simple enough to work as a view, then most of 
the time a view will be faster.  Generally the cases where functions are 
faster involve some type of complex operation, which you can use code in the 
function to cut down on processing. This get's less effective if you use an 
external procedural language, since the overhead of things like plperl or 
plphp is much more than that of plpgsql. Again, if you have some really 
complex operation that these languages make simple, it's often worth the 
tradeoffs. Note that for average use, all of this is pretty minimal anyway, 
so I'd probably recommend just doing it in whichever way you find most 
comfortable, and worry about optimizing things later if you find it's too 
slow.

-- 
Robert Treat
http://www.omniti.com
Internet Scalability Consulting