Re: Re: [SQL] aliases break my query

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Zeugswetter Andreas" <andreas.zeugswetter@telecom.at>
Cc: pgsql-hackers@postgresql.org
Date: 2000-05-26T21:34:28Z
Lists: pgsql-hackers
"Zeugswetter Andreas" <andreas.zeugswetter@telecom.at> writes:
> I think we could get agreement to not allow implicit from entries 
> if there is a from clause in the statement, but allow them if a from clause
> is missing altogether. The patch did not distinguish the two cases.

Hmm, that's a thought.  Taking it a little further, how about this:

"Emit a notice [or error if you insist] when an implicit FROM item is
added that refers to the same underlying table as any existing FROM
item."

95% of the complaints I can remember seeing were from people who got
confused by the behavior of "FROM table alias" combined with a reference
like "table.column".  Seems to me the above rule would catch this case
without being obtrusive in the useful cases.  Comments?

			regards, tom lane