Обсуждение: RES: [GENERAL] Select max field

Bob,

I think MAX aggregate function choose the maximum values of one field (or expression) in a set of rows. Not the max
vauesof many fields. 

----- Mensagem original -----
De:        Bob Kruger [SMTP:bkruger@mindspring.com]
Enviada em:        Quarta-feira, 10 de Fevereiro de 1999 16:43
Para:        pgsql-sql@postgreSQL.org; pgsql-general@postgreSQL.org
Assunto:        [GENERAL] Select max field



I am looking for a way to determine the largest value of a number of fields
in a tuple.

Example:  In a table with the fields id_no, t1, t2 ,t3 ,t4 ,t5
          Select the id_no and the greatest value from fields t1, t2, t3,
t4, t5.

I have tried the following, but with no success:

select id_no, max(t1, t2, t3, t4, t5) from table_1 ;

Anyone have any suggestions?

Thanks in advance for any assistance.

Regards - Bob