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Old October 18th, 2006, 02:36 PM posted to microsoft.public.access.tablesdbdesign
Phippsy
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Posts: 113
Default 1-1 relationship

Thank you all so much.
I suppose I am thinking of the primary table where referentioal integrity
has been set. Am I correct in thinking that the cascade only works one way -
ie from the 'Primary' (left hand) table. If you delete a record from the
'Primary' table it cascades through to the Child (Secondary) table but it
doesn't work if you delete a record from the Secondary table.

Debbie

"John Vinson" wrote:

On Tue, 17 Oct 2006 17:25:02 -0700, NetworkTrade
wrote:

Obviously they must share the same field ID...so neither/either is
inherently primary per se...in ones mind the table that is used most
frequently I tend to think of as the primary....


Well, as implemented in Access (and SQL/Server, Oracle, MySQL, and
others), you're mistaken; even one to one relationships have
directionality. If you are going to enforce referential integrity,
there must be a record in the "primary" or "left hand" table, and
there may or may not be a record in the child table. Strictly
speaking, it's a "One to (Zero or one)" relationship.

John W. Vinson[MVP]