Authors: Hoewon Kim, Seog Park
Tags: 1998, conceptual modeling
In decision supporting environments, a legacy operational system is needed to provide the additional facilities in order to manage the transaction that has the different characteristic from the traditional transaction. The most transactions that are used for decision support have a long-term read operation accessing a considerable portion of database. Therefore, the traditional concurrency control methods that are optimized to the on-line transaction processing cause the serious problem to the transaction management. The long delay of transaction processing cannot be avoided in those methods because of the lock conflict between the read operation of a decision supporting query and the write operation of an OLTP transaction. In this paper, transactions can be classified into two groups in decision supporting environment. One is the query session that consists of only read operations for decision support. The query session does not mind reading a possibly slightly old, but still consistent, version of the database. The other is the OLTP transaction that can have write operations for on-line transaction processing. According to our classification of transactions, we present a concurrency control algorithm that is called ‘Two Version Query Locking (2VQL)’. The 2VQL algorithm prevents a query session from blocking the operation of other transactions. It can be achieved by delaying the refresh process that exchanges old and new versions of an updated data. By our performance evaluation, the 2VQL algorithm is proved to be better than other legacy algorithms in the decision supporting of operational system.Read the full paper here: https://link.springer.com/chapter/10.1007/978-3-540-49121-7_14
