Обсуждение: Typo in 2.7 Aggregate Functions
The following documentation comment has been logged on the website: Page: https://www.postgresql.org/docs/15/tutorial-agg.html Description: Near the end of Chapter 2.7 Aggregate Functions of the documentation, the command FILTER is introduced. The full query is SELECT city, max(temp_lo), count(*) FILTER (WHERE temp_lo < 30) FROM weather GROUP BY city HAVING max(temp_lo) < 40; and the output shows a count value of 5. This is an error. In total we only have 3 rows in the table so far. Furthermore, none of the rows have temp_lo < 30. If I'm not mistaken, the count value should be 0. Thanks, Jimmy
PG Doc comments form <noreply@postgresql.org> writes:
> Near the end of Chapter 2.7 Aggregate Functions of the documentation, the
> command FILTER is introduced. The full query is
> SELECT city, max(temp_lo), count(*) FILTER (WHERE temp_lo < 30)
> FROM weather
> GROUP BY city
> HAVING max(temp_lo) < 40;
> and the output shows a count value of 5. This is an error.
Yeah :-(. This is already fixed in our source tree [1], as you
can see on the website if you look at the "devel" branch. But the
released-version docs won't update till our next releases, in
February.
Thanks for the report, anyway!
regards, tom lane
[1] https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=f05a5e0003edfec027ee10d09082667036862e1c