Re: A select DISTINCT query? - followup Q - Mailing list pgsql-general

"Harald Fuchs" <hf0114x@protecting.net> writes:

> If you want to select both columns, but have uniqueness over the first
> only, you can use a derived table:
>
> SELECT tbl.name, tbl.comment
> FROM tbl
> JOIN (SELECT name FROM tbl GROUP BY name HAVING count(*) = 1) AS t
>   ON t.name = tbl.name
>

Or use the first() aggregate since you know there's only going to be one
anyways:

select name, first(comment)
  from tbl
 group by name
having count(*) = 1

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  Gregory Stark
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