On Jan 7, 2008 4:03 PM, Emi Lu <emilu(at)encs(dot)concordia(dot)ca> wrote:
> Greetings,
>
> Version: PostgreSQL 8.0.13 on i686-pc-linux-gnu
>
> I have a table test(col1, col2, col3)
>
> For each row, I'd like to get the "max"(col1, col2, col3).
>
> For example, test(1, 5, 2)
> test(8, 1, 3)
> test(12, 1, 1)
>
>
> select ?max?(col1, col2, col3) as result;
> will return
>
> result
> -------
> 5
> 8
> 12
select max(col1) from table
union all
select max(col2) from table
union all
select max(col3) from table