Re: HAVING clause working in postgres 8.0, but not in 8.2

ujkavlade(at)gmail(dot)com writes:
> In PostgreSql 8.0, SELECT number FROM numbers HAVING number = 5;
> returns 5

> But in 8.2, it gives me the following error: ERROR: column
> "numbers.number" must appear in the GROUP BY clause or be used in an
> aggregate function.

> In the documentation, it says that HAVING can be used without GROUP BY
> or aggregate functions.

It can; whether it's useful or not is another question.

Per the 8.1 release notes:

* Fix HAVING without any aggregate functions or GROUP BY so that the
query returns a single group

Previously, such a case would treat the HAVING clause the same as
a WHERE clause. This was not per spec.

The above query is incorrect because it hasn't done anything to create
a grouped column.

regards, tom lane