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transactions T that hold locks on resources required
by U are blocked, by obeying both possible outcomes
of the blocked transactions T . This allows transac-
tions U to commit even if they conflict with pending
transactions T .
We have focused on database table definitions,
on arbitrary read- and write-operations, and we pro-
posed a rewrite rule system that allows all these kinds
of operations to be executed on a database that uses
Bi-State-Termination. Furthermore, we presented a
technique for checking typical integrity constraints
even in situations where a database using Bi-State-
Termination is not sure about its current state as pend-
ing transactions may commit or abort. Our proposed
technique for consistency constraint checking allows
checking whether or not a transaction may violate
given constraints. The experimental evaluation has
shown the feasibility of our constraints checker and
has proposed an optimization for checking time con-
suming multiple tuples constraints.
Altogether, the constraint checking technique pro-
posed in this paper is feasible and efficient, and it can
be done in combination with Bi-State-Termination
in mobile databases, even in case of network fail-
ures. This is why we consider the constraint check-
ing technique as a very important addition to Bi-
State-Termination, which is useful to integrate mobile
databases into business transactions.
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CONSTRAINT CHECKING FOR NON-BLOCKING TRANSACTION PROCESSING IN MOBILE AD-HOC
NETWORKS
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