Issue No. 04 - April (2004 vol. 16)
<p><b>Abstract</b>—In most current database systems, data is updated in-place. In order to support recovery and increase performance, write-ahead logging is used. This logging defers the in-place updates. However, sooner or later, the updates have to be applied to the database. Even if this is done as a batch operation, it can result in many nonsequential writes. In order to avoid this, another approach is to eliminate the database completely and use a <it>log-only</it> approach. In this case, the log is written contiguously to the disk, in a no--overwrite way using large blocks. When using the log-only approach keeping previous versions comes almost for free, and this approach is therefore particularly interesting for transaction-time temporal object database systems. Although the log-only approach in its basic form is relatively straightforward, it is not trivial to support features such as steal/no-force buffer management, fuzzy checkpointing, and fast commit. In this paper, we describe, in detail, algorithms and strategies for object and log management that make support for these features possible.</p>
Object database systems, temporal database systems, logging, recovery.
K. N?rv?, "The Vagabond Approach to Logging and Recovery in Transaction-Time Temporal Object Database Systems," in IEEE Transactions on Knowledge & Data Engineering, vol. 16, no. , pp. 504-518, 2004.