Dave Watts wrote: >> These tables are not a child-parent relationship. They are >> basically the same data with some variations of fields as >> time goes on. Is there an ER standard to express this type >> of relationship? >> > No, because there is no relationship between them, as "relationships" are > defined within a relational database. Do you have a suggestion how one could document this type of data model? I've since learned I may be making more of an 'data model|diagram' rather then an entity relationship diagram even though that is what Visio wants to call it.
I am trying to create documentation that shows how one ties all these tables together to create queries when wants 'all the records for Sacramento County where pesticide XYZ was used between 1975 and 2006' This would involve invoking the relationship with these Pesticide Use (PUR) tables with the normally associated tables of Products and Chemicals and Counties. But it also involves knowing how all these versions of the PUR tables are constructed and how that has changed from version to version. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Adobe® ColdFusion® 8 software 8 is the most important and dramatic release to date Get the Free Trial http://ad.doubleclick.net/clk;192386516;25150098;k Archive: http://www.houseoffusion.com/groups/CF-Talk/message.cfm/messageid:305250 Subscription: http://www.houseoffusion.com/groups/CF-Talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4
