> Why only honour referential integrity? Don't you want to honour check
> constraints, domain constraints, etc. ?? Perhaps 4. should read
> "Constraints must be honoured"; 3. becomes superfluous then, as
> primary & unique are constraints too.

------- End of Original Message -------

No transaction is allowed to commit changes that would cause any constraints
not to validate, if they could see exactly the data from all committed
transactions (previously fully committed, or currently past phase 1 of 2pc and
waiting in limbo), plus the transaction requesting commit. General enough?

(loophole that might not be a loophole:
- tx 1 starts
- tx 2 starts
- tx 1 creates master record with id 17
- tx 2 creates detail record with master_id 17, assuming deferred-constraints
- tx 1 commits
- tx 2 commits -> tx 2 couldn't see record from tx 1, but global database
state is still consistent after commit
)

-Philip