Sam Mason <s...@samason.me.uk> writes: > On Wed, Feb 18, 2009 at 10:30:12AM -0500, Tom Lane wrote: >> AFAIK, the Oracle behavior is just about entirely unrelated to the >> parser --- it's a matter of runtime comparison behavior. It is >> certainly *not* restricted to literal NULL/'' constants, which is the >> only case that a parser hack can deal with.
> 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 ||. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers