backend - microsoft access relationships: referential integrity different databases linked tables -


as far understanding goes, it's not possible enforce referential activity (and cascade updates) between tables come 2 different database (even if tables in split back-ends) right?

is necessary enforce referential activity if tables set correctly (ie normalized)? ask because if front end using (let's say) combo boxes row sources department table , control source stores foreign key (ie departmentid) in employee table, why matter if referential integrity enforced?

if matter absolutely must find way enforce referential integrity between tables come different database files.. there must way...

lastly, fix keep back-end tables in 1 single database file? every database uses employee table , department table.. rest of tables related other tables used in particular front-end database.

referential integrity isn't in reference lookup tables, it's parent/child tables or kind of vital relationship that, , should in same database. , tables should designed best fit application, whether use ri or not.

the whole point related table has key id other table points to, , if related record affected won't break relationship. lookup tables can structured have unique identifier, if original record lost, , new 1 added, though key have changed, unique identifier won't because you'll put in.

as general rule, if record in 1 table dependent on record in table, need referential integrity, , must in same database. way, database enforcing, , programmer doesn't have to.


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