1. A database server apparatus comprising: a data storage unit configured to store data; a committing procedure information storage unit configured to store committing procedure information for committing each of a plurality of transactions that updates data stored in the data storage unit; a data creating unit configured to create yet-to-be-committed update data from the stored data by executing a transaction for updating the data upon receipt of the transaction; a determining unit configured to determine whether there is another transaction that has source data which matches data of a transaction that is yet to be committed; and a committing unit configured to re-update the yet-to-be-committed update data and commit the transaction that is yet to be committed using the committing procedure information, when the determining unit determines that the data of the transaction that is yet to be committed matches the source data of the another transaction, and wherein the committing unit uses the source data to determine whether the another transaction is to update a same record as indicated in the source data.