David Fetter <david@fetter.org> writes:
> On Fri, Feb 19, 2010 at 12:07:42AM -0500, Tom Lane wrote:
>> SQL:1999 and later use a slightly different definition which is not
>> entirely upward compatible with SQL-92. In most cases, however,
>> PostgreSQL will interpret an ORDER BY or GROUP BY expression the
>> same way SQL:1999 does.
> The current SQL standard *supersedes* all previous ones.
That is the opinion of the SQL committee, all right, but it has got
precious little to do with the real world.
regards, tom lane