A new concurrency control scheme is introduced based on pre-committed method of transactions in mobile client. With this method, the mobile transactions are divided into two kinds: the pre-committed transaction and the request transaction. When the link is disconnected, the pre-committed transaction can update locally and the request transaction must wait until the link is reconnected. So this scheme can reduce the number of rejections and transactions commit time at mobile clients. At the same time, this method also can make the mobile transaction execute serializability.

mobile database; concurrency control; replication scheme; pro-committed