Dawn M. Wolthuis <dwolt_at_tincat-group.com> schrieb:
> Yes, you are absolutely right. In fact, the model I work with is more of a
> di-graph of data and instead of joins, it uses data trees (much like the
> web). This is accomplished with functions as well. Instead of using two
> different concepts -- sets/relations combined with operators, the model I
> work with uses functions in both cases.
Functions are one-way mappings. Many relationships in the world work
both ways. It certainly seems useful to distinguish these two kinds of
relationships, which relations + functions does but functions alone does
not.
Received on Fri Jan 09 2004 - 15:51:51 CST
