Re: doc question about column name alias

> Hi,
>     I'm translating 7.1.2's doc to Chinese, and got one question while
> doing these,
> in queries.sgml line 795:
>
> SELECT a AS b FROM table1 ORDER BY a;
>
> I think it should be:
>
> SELECT a AS b FROM table1 ORDER BY b;
>
> but from the context:"   References to column names in the FROM clause
> that are renamed in the select list are also allowed:"
> it seems the original is correct. Am I misunderstood? How the SQL
> standard saids?
> Thanks.

Both work:

    test=> select relname as x from pg_class order by relname;

and

    test=> select relname as x from pg_class order by x;

I am not sure which is more standards-compliant.

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