Hello mohamed, you wrote on Thu, 20 May 2021 13:07:57 +0000:
> Your answer deserves to be applied but my firebird data fields > to be sumed are either integer (16,32,64 bits) or numeric (x,y). > Numeric (x,y) is compatible with currency Var. Right, Numeric is compatible with currency, and (probabely) also with integer. But currency and integer are _not_ (directly) compatible, because one is a "whole number" type (integer), and the other is a _scaled_ number (currency, of course), which is lumped into the "real" types by fpc. In fact, currency is a 64 bit integer shifted "down" by (AFAIK) 4 decimal places, i.e. the integer value 10000 is equivalent to a currency value of "1", which incidentally would be equivalent to approximately a db numeric (20, 4) (20 digits w/ 4 decimal places). What this means is that to add an integer to such a "numeric" value, the integer value would have to be multiplied by 10000 first, whereas a currency value could be added directly. Things change "a bit" for numerics of other kinds, a (n, 3) numeric value, e.g., would require a scaling factor of 1000 against an integer, but a factor of 0.1 (!) aginst a currency value. These scaling operations are what makes the data types incompatible and what requires special handling for operations with the "numeric" db data type. I hope I got that all (mostly) right and could state it understandably. (BTW, all this has to be taken into account by a "variant" data type value, of course, what is what makes variants very complicated to handle and requires a lot of code to be implicitely added by the compiler and linker.) -- (Weitergabe von Adressdaten, Telefonnummern u.ä. ohne Zustimmung nicht gestattet, ebenso Zusendung von Werbung oder ähnlichem) ----------------------------------------------------------- Mit freundlichen Grüßen, S. Schicktanz ----------------------------------------------------------- _______________________________________________ mseide-msegui-talk mailing list mseide-msegui-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mseide-msegui-talk
