The reference table and reference field are the fields which specify the currency key or Unit of Measure. Suppose if the user specifies a currency amount say 1000$, the currency amount field would indicate the amount 1000 and the currency key indicates that the currency specified is in Dollars.
A reference field is needed for all currency and quantity fields as the figures in this field need a currency or unit. If you have no reference field and table for fields of this kind you will get a syntax error. This syntactic constraint reflects a semantic fact: A figure in a field does not tell you a lot if you do not know to which quantities or currencies the figure is related: It does not suffice to know that you have, for example, five items, but you need to know if you have five meters, five Euros, five pound etc. And this information is provided the reference field and table.
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Edited by: Alvaro Tejada Galindo on Apr 14, 2008 4:58 PM