My database consists of three main tables: one for the data which contains
only an item key, a date, and a value for each record; another for the item
keys, which has descriptions and details of the items in the data table; and
a third to give details on data sets that consist of a series of items listed
in the item table. Here is an example of the relationships:
Data table records:
ITEMKEYS: DATADATE: DATAVALUE:
ALLCAR_US 2/1/2006 20980
ALLCAR_US 3/1/2006 20111
Item Table Record:
ITEMKEY: ITEMNAME: TABLEID:
ALLCAR_US All Carriers of Freight in US 4
Last Table Record:
TABLEID: TABLENAME: DATEMODIFIED:
4 Canada-US Trade by Mode 4/1/2006
The relationships are: 1TABLE.ITEMKEYS = 2TABLE.ITEMKEY, and 2TABLE.TABLEID
= 3TABLE.TABLEID
My question is: Is it possible to have the DATEMODIFIED field in the last
table automatically enter the date on which the data contained in the data
table was last modified/updated? As it is now, i have to manually update the
data in the the data table, then manually update the date that i last
modified the data in the last table.
Please do not bother commenting on the field names - they are only examples,
and i'm not concerned about changing this element of my database.
Thanks,
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