[PHP-DB] MySQL SQL Query Help
I have a table: id fkid foobar 1 1 345yellow 2 1 34 red 3 2 3459 green 4 2 345brown I want to select the largest value of foo for a unique fkid, and return bar, the results ordered by bar. In this case, 345 is the largest value of foo for fkid 1, and 3459 is the largest for fkid 2. green comes before yellow. My desired result set would be: fkid foobar 2 3459 green 1 345yellow How would I write that in SQL? fkid and foo are ints, bar is a varchar. Beckman --- Peter Beckman Internet Guy [EMAIL PROTECTED] http://www.purplecow.com/ --- -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DB] MySQL SQL Query Help
Hi Try: SELECT fkid, MAX(foo), bar FROM table GROUP BY fkid ORDER BY bar DESC Niel -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP-DB] MySQL SQL Query Help
select max(bar) from mytable where unique fkid order by bar asc as far as I remember!! -Original Message- From: Peter Beckman [mailto:[EMAIL PROTECTED] Sent: Lunes, 13 de Noviembre de 2006 04:59 p.m. To: PHP-DB Mailing List Subject: [PHP-DB] MySQL SQL Query Help I have a table: id fkid foobar 1 1 345yellow 2 1 34 red 3 2 3459 green 4 2 345brown I want to select the largest value of foo for a unique fkid, and return bar, the results ordered by bar. In this case, 345 is the largest value of foo for fkid 1, and 3459 is the largest for fkid 2. green comes before yellow. My desired result set would be: fkid foobar 2 3459 green 1 345yellow How would I write that in SQL? fkid and foo are ints, bar is a varchar. Beckman --- Peter Beckman Internet Guy [EMAIL PROTECTED] http://www.purplecow.com/ --- -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php Este mensaje es exclusivamente para el uso de la persona o entidad a quien esta dirigido; contiene informacion estrictamente confidencial y legalmente protegida, cuya divulgacion es sancionada por la ley. Si el lector de este mensaje no es a quien esta dirigido, ni se trata del empleado o agente responsable de esta informacion, se le notifica por medio del presente, que su reproduccion y distribucion, esta estrictamente prohibida. Si Usted recibio este comunicado por error, favor de notificarlo inmediatamente al remitente y destruir el mensaje. Todas las opiniones contenidas en este mail son propias del autor del mensaje y no necesariamente coinciden con las de Radiomovil Dipsa, S.A. de C.V. o alguna de sus empresas controladas, controladoras, afiliadas y subsidiarias. Este mensaje intencionalmente no contiene acentos. This message is for the sole use of the person or entity to whom it is being sent. Therefore, it contains strictly confidential and legally protected material whose disclosure is subject to penalty by law. If the person reading this message is not the one to whom it is being sent and/or is not an employee or the responsible agent for this information, this person is herein notified that any unauthorized dissemination, distribution or copying of the materials included in this facsimile is strictly prohibited. If you received this document by mistake please notify immediately to the subscriber and destroy the message. Any opinions contained in this e-mail are those of the author of the message and do not necessarily coincide with those of Radiomovil Dipsa, S.A. de C.V. or any of its control, controlled, affiliates and subsidiaries companies. No part of this message or attachments may be used or reproduced in any manner whatsoever. -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DB] MySQL SQL Query Help
Actually, that should not work, it should give you an error. This should work: SELECT `fkid`,max(`foo`) as foo,`bar` FROM `test2` GROUP BY `fkid` ORDER BY `bar` ASC Miguel Guirao wrote: select max(bar) from mytable where unique fkid order by bar asc as far as I remember!! -Original Message- From: Peter Beckman [mailto:[EMAIL PROTECTED] Sent: Lunes, 13 de Noviembre de 2006 04:59 p.m. To: PHP-DB Mailing List Subject: [PHP-DB] MySQL SQL Query Help I have a table: id fkid foobar 1 1 345yellow 2 1 34 red 3 2 3459 green 4 2 345brown I want to select the largest value of foo for a unique fkid, and return bar, the results ordered by bar. In this case, 345 is the largest value of foo for fkid 1, and 3459 is the largest for fkid 2. green comes before yellow. My desired result set would be: fkid foobar 2 3459 green 1 345yellow How would I write that in SQL? fkid and foo are ints, bar is a varchar. Beckman --- Peter Beckman Internet Guy [EMAIL PROTECTED] http://www.purplecow.com/ --- -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DB] MySQL SQL Query Help
On Mon, 13 Nov 2006, [EMAIL PROTECTED] wrote: Actually, that should not work, it should give you an error. This should work: SELECT `fkid`,max(`foo`) as foo,`bar` FROM `test2` GROUP BY `fkid` ORDER BY `bar` ASC Yes, but if the data is in a different order that fails and doesn't maintain row order: mysql create temporary table test2 (id tinyint,fkid tinyint, foo smallint, bar varchar(20)); mysql insert into test2 values (1,1,34,'red'), (2,1,345,'yellow'), (3,2,345,'brown'), (4,2,3459,'green'); mysql select * from test2; +--+--+--++ | id | fkid | foo | bar| +--+--+--++ |1 |1 | 34 | red| |2 |1 | 345 | yellow | |3 |2 | 345 | brown | |4 |2 | 3459 | green | +--+--+--++ mysql SELECT `fkid`,max(`foo`) as foo,`bar` FROM `test2` GROUP BY `fkid` ORDER BY `bar` ASC; +--+--+---+ | fkid | foo | bar | +--+--+---+ |2 | 3459 | brown | |1 | 345 | red | +--+--+---+ 2 rows in set (0.00 sec) Notice how 3459 is supposed to be green but reports brown, and 345 should be yellow but reports red? Any other solutions that maintain row integrity? Beckman Miguel Guirao wrote: select max(bar) from mytable where unique fkid order by bar asc as far as I remember!! -Original Message- From: Peter Beckman [mailto:[EMAIL PROTECTED] Sent: Lunes, 13 de Noviembre de 2006 04:59 p.m. To: PHP-DB Mailing List Subject: [PHP-DB] MySQL SQL Query Help I have a table: id fkid foobar 1 1 345yellow 2 1 34 red 3 2 3459 green 4 2 345brown I want to select the largest value of foo for a unique fkid, and return bar, the results ordered by bar. In this case, 345 is the largest value of foo for fkid 1, and 3459 is the largest for fkid 2. green comes before yellow. My desired result set would be: fkid foobar 2 3459 green 1 345yellow How would I write that in SQL? fkid and foo are ints, bar is a varchar. Beckman --- Peter Beckman Internet Guy [EMAIL PROTECTED] http://www.purplecow.com/ --- -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php --- Peter Beckman Internet Guy [EMAIL PROTECTED] http://www.purplecow.com/ --- -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DB] MySQL SQL Query Help
Peter Beckman wrote: On Mon, 13 Nov 2006, [EMAIL PROTECTED] wrote: Actually, that should not work, it should give you an error. This should work: SELECT `fkid`,max(`foo`) as foo,`bar` FROM `test2` GROUP BY `fkid` ORDER BY `bar` ASC Yes, but if the data is in a different order that fails and doesn't maintain row order: mysql create temporary table test2 (id tinyint,fkid tinyint, foo smallint, bar varchar(20)); mysql insert into test2 values (1,1,34,'red'), (2,1,345,'yellow'), (3,2,345,'brown'), (4,2,3459,'green'); mysql select * from test2; +--+--+--++ | id | fkid | foo | bar| +--+--+--++ |1 |1 | 34 | red| |2 |1 | 345 | yellow | |3 |2 | 345 | brown | |4 |2 | 3459 | green | +--+--+--++ mysql SELECT `fkid`,max(`foo`) as foo,`bar` FROM `test2` GROUP BY `fkid` ORDER BY `bar` ASC; +--+--+---+ | fkid | foo | bar | +--+--+---+ |2 | 3459 | brown | |1 | 345 | red | +--+--+---+ 2 rows in set (0.00 sec) Notice how 3459 is supposed to be green but reports brown, and 345 should be yellow but reports red? Any other solutions that maintain row integrity? You might have to go a subquery. (I'm not great at subqueries so there would have to be a better way to write this anyway). This works in postgresql: select fkid, foo, bar from test2 t2 where (select max(foo) from test2 t1 where t1.fkid=t2.fkid)=foo; but mysql won't let you reference the same table inside outside: mysql select fkid, foo, bar from test2 t2 where (select max(foo) from test2 t1 where t1.fkid=t2.fkid)=foo; ERROR 1137 (HY000): Can't reopen table: 't2' http://dev.mysql.com/doc/refman/5.0/en/subqueries.html The mysql mailing list might have better ideas.. -- Postgresql php tutorials http://www.designmagick.com/ -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
