<Jay>
So i have table A (keyed by identity column), and index A (keyed by key1,
key2).

I have table B (keyed by identity column) and index B (keyed by key1, key2
- same defined keys as in index A)

table B is really just an "additional information" table for the rows and
keys defined in table A.

How can I apply some kind of referential integrity over table B to allow
table B keyed rows to be deleted if table A similar keyed rows are
deleted?
<snip>

... this could be done by a referential constraint - if the matching key of table A is unique! Better design would be if the matching key is primary key of A.

</snip>
Likewise if table A key value changes, table B key values change.
<snip>

this is impossible with referential constraints (not allowing changes of the parent key) and in contradiction to the concept of sql at all: a primary key must not change!!!

</snip>
I know I am probably dreaming.
</Jay>

... seems to be a nightmare to me!

Dieter

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