Perhaps a little on the hacky side but....
select count(1) from some_table group by identno order by 1 desc limit 1;
If the result is anything other than 1, it's not unique.
Sorry for the hacky nature, this is the "thought about it for 10
seconds" version. :-)
-Fran
Peter E. Chen wrote:
>Can anyone tell me what is the easiest way for me to tell if a column is
>unique or not? I tried using DISTINCT ON and COUNT together in a SELECT
>statement, but I can't seem to get the query to work:
>
>SELECT DISTINCT ON (identno) count(identno) FROM some_table;
>
>I was trying to figure out if the # of unique entries for a particular
>column is equal to the # of total entries for that column.
>
>Any suggestions?
>
>Peter
>
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