Friday, February 25, 2011, 12:53:08 AM you wrote:
> select distinct on (a, b, c)
> a, b c, time_stamp, value
Without the comma, you declare 'b AS c'
> from data
> order by a, b, c, time_stamp desc;
> The output produced is the same as this query:
> select distinct on (a, b)
> a, b, time_stamp, value
> from data
> order by a, b, time_stamp desc;
the 'c' is optimized away, since it is an alias for b, and thus redundant
for the distinct.
> Not sure if this is considered a parser bug or not, but it feels slightly
> odd not to get an error.
No error, just plain SQL :-)
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