Databases Reference
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fIGure 14.4
Load Market Basket BI Table with Correlation Entity.
time variant parent Entity_Key. If that inequality statement were changed
to DRIVER_INSTANCE_KEY<>DRIVER_INSTANCE_KEY, then each
Instance_Key would be juxtaposed with its time variant parent Entity_
Key, excluding its own portion of that Entity_Key. This is a subtlety that
can cause more confusion than any value it adds for analysts who don't
understand the presence of a row juxtaposing an Instance_Key and its
parent Entity_Key. For that reason, and the limited value it provides, the
inequality statement DRIVER_ENTITY_KEY <> CORR_ENTITY_KEY
is often the preferred approach.
