Re: What's new?

On 30/01/2010 00:31, Peter Geoghegan wrote:

>> I had a play with the query Greg Stark produced that generates the
>> Mandelbrot set - really cool! Haven't needed to look at window functions
>> yet, but keeping them in the back of my mind as a tool.
>
> Wasn't that David Fetter? You might be surprised at the broad

Yes, I think you're right, it was - I copied it from a set of slides
from a talk that Greg gave on recursive queries.

> applicability of CTEs (recursive CTEs not so much) - I was. They've
> sprung up a lot in my production code. I was able to use a recursive
> CTE very effectively to populate a graph of historic stock quantities
> day-by-day, working backwards from the authoritative current qty in
> stock - doing this without recursive CTEs would have been very
> difficult. They make complex queries more manageable too.

Cool! Most of the queries I've been writing in the current project are
very simple - simple inserts and updates, no complex joins. However, I'm
planning on revisiting an online aircraft booking system I wrote for the
Flying Club a while back, which uses some reasonably complex queries to
build time-sheets and other stuff... I had to use a plpgsql function in
the end, but I'd be interested to see if I can use CTEs to simplify it
and maybe improve performance. I can post the code if you're interested.

Ray.

--
Raymond O'Donnell :: Galway :: Ireland
rod(at)iol(dot)ie