Hi
i have an table where i store addresses of my contact. A contact may change address and i want to keep track of these changes in order to be able,for example, to determine what address a contact had on a certain data. Is there some pattern describing this kind of temporal issue?
thanks

i'm not sure what a pattern is, but one common way of doing what you ask is to have two additional datetime columns in the table, effective_from and effective_to

effective_to would be set to NULL for the current address

when the contact changes, set effective_to to the change datetime, and insert a new row with the change datetime as effective_from and NULL as effective_to

to find the current address, just use to find the address at any time in the past, use

thank you very much.