MS Access vs IS NULL (was Re: [BUGS] Bug in SQL functions that use a NULL parameter directly)

Started by Tom Lanealmost 25 years ago2 messages
#1Tom Lane
tgl@sss.pgh.pa.us

Stephan Szabo <sszabo@megazone23.bigpanda.com> writes:

Because of Access's brokenness, the parser or some other layer of the
code "fixes" explicit = NULL (ie, in the actually query string) into
IS NULL which is the correct way to check for nulls.
Because your original query was = $1, it doesn't do the mangling of the
SQL to change into IS NULL when $1 is NULL. The fact that we do that
conversion at all actually breaks spec a little bit but we have little
choice with broken clients.

It seems to me that we heard awhile ago that Access no longer generates
these non-spec-compliant queries --- ie, it does say IS NULL now rather
than the other thing. If so, it seems to me that we ought to remove the
parser's = NULL hack, so that we have spec-compliant NULL behavior.

Anyone recall anything about that? A quick search of my archives didn't
turn up the discussion that I thought I remembered.

regards, tom lane

#2Thomas Lockhart
lockhart@alumni.caltech.edu
In reply to: Tom Lane (#1)
Re: MS Access vs IS NULL (was Re: [BUGS] Bug in SQL functions that use a NULL parameter directly)

Anyone recall anything about that? A quick search of my archives didn't
turn up the discussion that I thought I remembered.

Hmm. Maybe now we know what you dream about at night ;)

- Thomas