Re: WIP: hooking parser - Mailing list pgsql-hackers

From Peter Eisentraut
Subject Re: WIP: hooking parser
Date
Msg-id 499E8A8F.9090502@gmx.net
Whole thread Raw
In response to Re: WIP: hooking parser  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: WIP: hooking parser
List pgsql-hackers
Tom Lane wrote:
>> How about introducing a "varchar2" type as in Oracle?
> 
> Maybe.  I think right now we don't allow input functions to decide
> that a non-null input string should be converted to a NULL, but
> that might be fixable.  It'd still be an ugly mess though, since
> I suspect you'd have to introduce a whole structure of varchar2
> functions/operators paralleling text.  For example, what is Oracle's
> handling of || ?  AFAICS they can't be standards compliant there,
> which means you need a varchar2-specific nonstrict implementation
> of ||, and then to make that work the way Oracle users would expect,
> varchar2-ness rather than text-ness would have to propagate through
> anything else that might be done to a column before it reaches the ||.

Curiously enough, Oracle has it so that || of null arguments treats the 
arguments as empty string.

It's beyond comprehension.

But yeah, a varchar2 type with a full set of functions and operators 
could work.  If you choose not to bother with supporting the char type.


pgsql-hackers by date:

Previous
From: Peter Eisentraut
Date:
Subject: Password prompting business
Next
From: ohp@pyrenet.fr
Date:
Subject: Re: pg_restore new option -m