Is it the same in all database servers? Teddy, Teddy's Center: http://teddy.fcc.ro/ Email: [EMAIL PROTECTED]
----- Original Message ----- From: "gerald_clark" <[EMAIL PROTECTED]> To: "Octavian Rasnita" <[EMAIL PROTECTED]> Cc: "Stefan Hinz, iConnect (Berlin)" <[EMAIL PROTECTED]>; "MySQL" <[EMAIL PROTECTED]> Sent: Friday, January 24, 2003 4:12 PM Subject: Re: Is it normal? Any calculation involving a floating point number will be imprecise. It does not mater what column types are involved. Octavian Rasnita wrote: >And does anyone know what column type I should use if I want a precise >calculation? >I've even tried with text and blob, but they are not working either. >Only the int type is precise? > >Thanks. > >Teddy, >Teddy's Center: http://teddy.fcc.ro/ >Email: [EMAIL PROTECTED] > >----- Original Message ----- >From: "Stefan Hinz, iConnect (Berlin)" <[EMAIL PROTECTED]> >To: "Octavian Rasnita" <[EMAIL PROTECTED]>; "MySQL" <[EMAIL PROTECTED]> >Sent: Monday, January 20, 2003 11:42 PM >Subject: Re: Is it normal? > > >Octavian, > > > >>mysql> create table test(id float); >>mysql> insert into test values(1.123), (3.1495); >>mysql> select * from test where id=1.123; >>Empty set (0.00 sec) >>Shouldn't this last query show me the record that has the id=1.123? >> >> > >Well ... 1.123 is greater than 1.123, see: > >mysql> select id from octavian where id > 1.123; >+--------+ >| id | >+--------+ >| 1.123 | >| 3.1495 | >+--------+ >2 rows in set (0.00 sec) > >Now here's why. Floats are simply not precise: > >mysql> select id*10000 from octavian where id > 1.123; >+-----------------+ >| id*10000 | >+-----------------+ >| 11230.000257492 | <---------- >| 31494.998931885 | >+-----------------+ >2 rows in set (0.00 sec) > > > >>What query should I use to do this? >> >> > >I leave this one to Paul or one of the other gurus. > >Regards, >-- > Stefan Hinz <[EMAIL PROTECTED]> > Geschäftsführer / CEO iConnect GmbH <http://iConnect.de> > Heesestr. 6, 12169 Berlin (Germany) > Tel: +49 30 7970948-0 Fax: +49 30 7970948-3 > >----- Original Message ----- >From: "Octavian Rasnita" <[EMAIL PROTECTED]> >To: "MySQL" <[EMAIL PROTECTED]> >Sent: Monday, January 20, 2003 9:34 AM >Subject: Is it normal? > > > > >>Hi all, >> >>I've tried the following SQL queries: >> >>mysql> create table test(id float); >>Query OK, 0 rows affected (0.00 sec) >> >>mysql> insert into test values(1.123), (3.1495); >>Query OK, 2 rows affected (0.01 sec) >>Records: 2 Duplicates: 0 Warnings: 0 >> >>mysql> select * from test where id=1.123; >>Empty set (0.00 sec) >> >>Shouldn't this last query show me the record that has the id=1.123? >> >>What query should I use to do this? >> >>Thank you. >> >> >> >>Teddy, >>Teddy's Center: http://teddy.fcc.ro/ >>Email: [EMAIL PROTECTED] >> >> >> >>--------------------------------------------------------------------- >>Before posting, please check: >> http://www.mysql.com/manual.php (the manual) >> http://lists.mysql.com/ (the list archive) >> >>To request this thread, e-mail <[EMAIL PROTECTED]> >>To unsubscribe, e-mail >> >> ><[EMAIL PROTECTED]> > > >>Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php >> >> >> > > > > >--------------------------------------------------------------------- >Before posting, please check: > http://www.mysql.com/manual.php (the manual) > http://lists.mysql.com/ (the list archive) > >To request this thread, e-mail <[EMAIL PROTECTED]> >To unsubscribe, e-mail <[EMAIL PROTECTED]> >Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php > > > > --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
