Re: problem with query and group by error

Susan Cassidy-3 wrote
> Someone said something about
> "Yes, except those that are inside the aggregate."
> but I don't have an aggregate specified.

So every column then...

As soon as you add "group by" the rule becomes - every column is either a
group determinate or is aggregated. If you simply want to remove duplicates
you can write:

Select distinct ... From

No group by clause required and every output column is used to create an
implicit non-duplicated group.

I haven't tried to figure out what you are trying to do with this query so I
don't know which, if either, form is more correct but grouping without
aggregates is unusual and I also find that using distinct is not that common
a need of you have a correctly normalized database. IOW you should not use
group by or distinct to "make the query work" but only if you
know/understand why doing so is necessary.

David J.

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