Re: Column aliases in WHERE clauses

On Tue, Sep 18, 2012 at 2:53 AM, Eden Cardim <eden(at)insoli(dot)de> wrote:

> >>>>> "Craig" == Craig Ringer <ringerc(at)ringerc(dot)id(dot)au> writes:
>
> Craig> I just wish they hadn't written it backwards!
>
> Craig> It'd be much less confusing were it formulated as something
> Craig> like:
>
> Craig> SELECT FROM thetable WHERE first_letter > 'a' RESULTS
> Craig> left(value,1) AS first_letter
>
> Craig> or something, where the order is more obvious. I really
> Craig> dislike the way SQL is written not-quite-backwards.
>
> It's not "written backwards", it's plain natural language semantics:
> "give me the first letter of all records where the first letter is
> greater than a". Refining a set is better done walking from the more
> general set to a subset, not the other way around, IMO: "give me all
> persons that are females and over the age of 20". Mathematical set
> builder notation does this in a similar fashion, for the same reason.
>
>
Natural language semantics will get you into trouble though. After all, I
think Lisp follows natural language semantics remarkably closely if your
natural language is Irish Gaelic....

Best Wishes,
Chris Travers