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From: Tom Lane <[email protected]>
To: [email protected]
Cc: [email protected]
Cc: [email protected]
Subject: Re: BUG #7543: Invalid table alias: DELETE FROM table *
Date: Sun, 16 Sep 2012 23:58:06 -0400
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>

[email protected] writes:
> I sometime see my users delete all rows from a table using a command like
> this:

> DELETE FROM customer *;

> The question is: what is the star? Is it a table alias or an
> output_expression?

Neither; it specifies to search the table and its inheritance children,
ie, the opposite of ONLY.  This has been the default behavior (unless
you change the setting of sql_inheritance) for many years, so "*" has
largely fallen into disuse; but it's still accepted.

However ... I went looking for documentation on this point, and I'm
darned if I can find any.  There certainly used to be some, but
apparently somebody got over-eager about editing the docs to reflect
the modern default behavior.  The "*" doesn't even appear in the syntax
summaries for most of the commands where it's allowed, which is flat
wrong --- anywhere you can write "ONLY tablename", it's valid to write
"tablename*" instead.

So we have some docs work to do.  Thanks for pointing it out.

			regards, tom lane




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