Main Page | See live article | Alphabetical index In computer science, in the field of databases, non-lock concurrency control is concurrency control method used in relational databases without using locking. There are several non-lock concurrency control methods: Optimistic concurrency control Timestamp-based concurrency control Multiversion concurrency control They involve the use of timestamps on transaction to determine transaction priority. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.