Kevin Grittner wrote:
On Thu, Aug 23, 2007 at  3:01 PM, in message <[EMAIL PROTECTED]>,
Tom Lane <[EMAIL PROTECTED]> wrote:
The only argument I've
heard that carries much weight with me is that it eases porting from
other DBMS's that allow this.  Are there any others besides Oracle?
select * from (select f1 from t)
In Sybase: com.sybase.jdbc2.jdbc.SybSQLException: The derived table expression is missing a correlation name. Check derived table syntax in the Reference Manual.
Error code: 11753
SQL state: ZZZZZ


The really funny thing is that pgsql, mysql and at least sybase
*explicitly* dissallow the no-alias case. Which shows that
  .) This seems to be common source of confusion and errors.
  .) Aliasless-Subqueries wouldn't lead to ambigous grammras in those databases.
     Otherwise, you'd expect to get some more generic syntax error, and not
     the very explicit "No alias, but expected one".

I agree with Tom - knowing *why* the standard committee disallows that syntax -
and why everybody except oracle chose to agree with it would be quite 
interesting.

greetings, Florian Pflug


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