Re: "<query expression body> ::= <joined table>" grammar rule not accepted by Postgres

On 06/15/2011 10:59 PM, Tom Lane wrote:
> Clem Dickey<dickeycl(at)us(dot)ibm(dot)com> writes:
>> This expression is (I think) a well-formed query, but is rejected by
>> Postgresql 8.4 (t is a table name).
>
>> t t1 NATURAL JOIN t t2;
>
> Hmm ... I think you are looking at SQL92 or SQL99.

> [ digs a bit more... ] Ah, here we are: Annex E of SQL:2003 calls out
> various incompatibilities from SQL:99, notably
>
> 6) In ISO/IEC 9075-2:1999, a<query expression body>,<query
> term>, or<query primary> could consist of a<joined
> table>. None of those three elements can consist of a<joined
> table> in this edition of ISO/IEC 9075.

Thanks for the research. I was indeed reading from SQL99, which was
current the last time I used SQL. I'll have to spring for a newer
standard (or the equivalent).