The previous method would always leave a gap between the last value and the
new one due to how you have to update the sequence values. To remove gaps in
all situations, the options are to alter the USER_SEQUENCES table or just
drop the sequence and recreate it. The prior requires elevated priveleges
and the latter can break attached objects. Since we don't attach objects to
the sequences, we won't have any problems doing it for the tests.
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