Re: the '::' cast doesn't work in the FROM clause

On Aug 29, 2011, at 5:02 PM, Kevin Grittner wrote:

> Alexey Klyukin <alexk(at)commandprompt(dot)com> wrote:
>
>> Function calls can appear in the FROM clause. (This is especially
>> useful for functions that return result sets, but any function can
>> be used.) This acts as though its output were created as a
>> temporary table for the duration of this single SELECT command.
>
> It doesn't say that operators which provide equivalent functionality
> to functions can also be used.

I agree, but why is it possible to use the type casting with CAST there? Doesn't this break the promise of equivalency between the 'CAST .. ' and '::'?

select val from CAST(random() as integer) as val;
val
-----
1
(1 row)

--
Alexey Klyukin http://www.commandprompt.com
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