> -----Original Message----- > From: Obed Soto Déctor [mailto:[EMAIL PROTECTED] > Sent: Monday, July 17, 2006 7:28 PM > To: mysql@lists.mysql.com > Subject: problem with double data > > Hi, i'm sorry for my english, i'm from México and i'm gonna do my best, > > i've made a store procedure but i have some problems becouse when a > make a simple operation with double datas the result is not what i > wait. > > look > > cantidad_origen = 30.5 > cantidad_ = 30.4 > suma = 0 > > UPDATE detalle_tanque set cantidad = ( cantidad_origen - cantidad_ - > suma ) where id_detalle_transaccion = id_detalle_transaccion_origen > and ctl_no=ctl_no_origen; > > cantidad = 0.100000000000001 >
Looks like your standard floating-point rounding error. See http://dev.mysql.com/doc/refman/5.0/en/numeric-type-overview.html which says: "A double-precision floating-point number is accurate to approximately 15 decimal places." If I counted right, the "errant 1" at the end is in place 15, so that is accurate to approximately 15 places. Tim > i don't know what .... im waiting > > cantidad = 0.1 > > thanks any help will be good for me > > > > -- > http://www.obed.org.mx ---> blog > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
