Hello Benoit, It might be useful to supply your table definitions. I did the following test and I can't find a problem. I am using 10.0.19-MariaDB. CREATE TABLE t1 ( col1 INT, # have also tried defined as VARCHAR. No problem either. col2 INT ); INSERT INTO `t1` (`col1`, `col2`) VALUES('8','58'); INSERT INTO `t1` (`col1`, `col2`) VALUES('8','48'); INSERT INTO `t1` (`col1`, `col2`) VALUES('4','63'); INSERT INTO `t1` (`col1`, `col2`) VALUES('9','53'); INSERT INTO `t1` (`col1`, `col2`) VALUES('2','36'); INSERT INTO `t1` (`col1`, `col2`) VALUES('0','12'); INSERT INTO `t1` (`col1`, `col2`) VALUES('3','2'); INSERT INTO `t1` (`col1`, `col2`) VALUES('0','2'); INSERT INTO `t1` (`col1`, `col2`) VALUES('0','6'); INSERT INTO `t1` (`col1`, `col2`) VALUES('0','2'); INSERT INTO `t1` (`col1`, `col2`) VALUES('0','9'); INSERT INTO `t1` (`col1`, `col2`) VALUES('0','44'); INSERT INTO `t1` (`col1`, `col2`) VALUES('14','63'); INSERT INTO `t1` (`col1`, `col2`) VALUES('0','96'); INSERT INTO `t1` (`col1`, `col2`) VALUES('7','43'); INSERT INTO `t1` (`col1`, `col2`) VALUES('4','66'); INSERT INTO `t1` (`col1`, `col2`) VALUES('2','43'); INSERT INTO `t1` (`col1`, `col2`) VALUES('2','66'); INSERT INTO `t1` (`col1`, `col2`) VALUES('0','63'); INSERT INTO `t1` (`col1`, `col2`) VALUES('6','48'); INSERT INTO `t1` (`col1`, `col2`) VALUES('2','52'); SELECT col1, col2, col1 + col2 FROM t1; # Correctly returns 96 SELECT MAX(col1 + col2) FROM t1; Cheers, Rhys -----Original Message----- From: Maria-discuss [mailto:maria-discuss-bounces+rhys.campbell=tradingscreen.com@lists.launchpad.net] On Behalf Of Benoit Panizzon Sent: 19 June 2015 09:59 To: maria-discuss@lists.launchpad.net Subject: [Maria-discuss] Bug in MAX() function? Hi all I stumbled over that problem, while trying to graph mail traffic.. I have two different counters for emails sent with authentication and without. Aggregated per hour. I would like to total the both values per row, to create a graph of outgoing emails per hour. MariaDB [maildb]> select mail_out_anon,mail_out_auth from domaincounters; +---------------+---------------+ | mail_out_anon | mail_out_auth | +---------------+---------------+ | 8 | 58 | | 8 | 48 | | 4 | 63 | | 9 | 53 | | 2 | 36 | | 0 | 12 | | 3 | 2 | | 0 | 2 | | 0 | 6 | | 0 | 2 | | 0 | 9 | | 0 | 44 | | 14 | 63 | | 0 | 96 | | 7 | 43 | | 4 | 61 | | 2 | 43 | | 2 | 66 | | 0 | 86 | | 6 | 77 | | 6 | 55 | | 0 | 63 | | 6 | 48 | | 2 | 52 | +---------------+---------------+
select mail_out_anon+mail_out_auth as mail_out_total from domaincounters;
+-----------------------------+ | mail_out_anon+mail_out_auth | +-----------------------------+ | 70 | | 56 | | 67 | | 62 | | 38 | | 12 | | 5 | | 2 | | 6 | | 2 | | 9 | | 44 | | 77 | | 96 | | 50 | | 65 | | 45 | | 68 | | 86 | | 83 | | 61 | | 63 | | 54 | | 54 | +-----------------------------+ Now I need the max value of that addition to auto-scale the graph. MariaDB [maildb]> select MAX(mail_out_anon+mail_out_auth) +----------------------------------+ | MAX(mail_out_anon+mail_out_auth) | +----------------------------------+ | 187 | +----------------------------------+ What did MariaDB count here? I was expecting a value 96 which is the largest value of all the additions. Also trying various ways of first using GREATEST() always returns a way to high value. Is it a bug, or did I do something wrong? Mit freundlichen Grüssen Benoit Panizzon -- I m p r o W a r e A G - ______________________________________________________ Zurlindenstrasse 29 Tel +41 61 826 93 07 CH-4133 Pratteln Fax +41 61 826 93 02 Schweiz Web http://www.imp.ch ______________________________________________________ _______________________________________________ Mailing list: https://launchpad.net/~maria-discuss Post to : maria-discuss@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-discuss More help : https://help.launchpad.net/ListHelp