Re: ODBC 3.0 functions (UCASE, LCASE, etc.) - Mailing list pgsql-general

Bruce Momjian writes:

> This is clearly a good idea.  It is easy to create SQL functions as
> synonyms for existing functions.  You can even alter the arguments.  I
> would encourage anyone who wants to start coding an SQL file of
> compatibility functions.

src/interfaces/odbc/odbc.sql

RTFM rules ;-)

>
> > On Thu, 3 May 2001, Bruce Momjian wrote:
> >
> > >
> > > This sounds good.  Would these exist in ODBC or in the backend?  My
> > > understanding is that these are best done in ODBC.
> >
> > It's not so much an ODBC problem *per se*, but, rather, that many
> > databases offer 'functions' (some from standards, some made up) that we
> > don't have. (The ODBC specs just happen to recommend a large slew of
> > them.)
> >
> > I'd think these would have to be backend functions, but probably best not
> > actually in the backend source.
> >
> > Since we can create functions easily, and since few of these things are
> > actually new features, but re-named/re-ordered functions we already have,
> > it wouldn't seem too onerous to make wrappers around these, or hook some
> > of these in as aliases for existing functions/types.
> >
> > Things like:
> >
> >  - aliasing int to mediumint
> >  - alias textcat to concat
> >  - iif( condition, true_expr, false_expr )
> >  - first(), last() aggregates
> >  - std() as an alias for stddev()
> >
> > Yes, some of these *are* ugly, non-standard forms used by other databases.
> > Read on for why I still think it could be a good idea.
> >
> > Some things we have (like existing odbc.sql file in src/interfaces/odbc),
> > or in contrib/ (like soundex) are probably missed by many users. (And,
> > although this is probably intentional, are left off of MySQL's crash-me).
> >
> > Perhaps a useful form would be a folder of function wrappers, group by
> > 'competitor':
> >
> >   oracle.sql
> >   mysql.sql
> >   access.sql
> >   odbc.sql
> >
> > which would contain the wrappers functions for these systems. Of course,
> > we can't mimic *everything* (at least not in plpgsql functions ;-) )
> > but we might be able to do much better.
> >
> >
> > I know it seems like a trivial thing, but it's not too infrequent that
> > I'll hear someone chatting online/posting a follow-up message about how
> > they've evaluated PostgreSQl, or another product, but didn't use it
> > because we lacked feature foo(), when it's there, and just called feature
> > bar().
> >
> > Anyway, this isn't an itch that I *need* to scratch -- right now,
> > all I use in the office is PostgreSQL for backend work :-). But I think in
> > the 'how easy are we to evaluate and use' department, it could be a small,
> > but helpful win.
> >
> > --
> > Joel Burton   <jburton@scw.org>
> > Director of Information Systems, Support Center of Washington
> >
> >
>
>

--
Peter Eisentraut   peter_e@gmx.net   http://funkturm.homeip.net/~peter