In
Computer Science
Computer science is the study of computation, information, and automation. Computer science spans Theoretical computer science, theoretical disciplines (such as algorithms, theory of computation, and information theory) to Applied science, ...
, in the field of
database
In computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and a ...
s, non-lock concurrency control is a
concurrency control
In information technology and computer science, especially in the fields of computer programming, operating systems, multiprocessors, and databases, concurrency control ensures that correct results for concurrent operations are generated, whil ...
method used in
relational database
A relational database (RDB) is a database based on the relational model of data, as proposed by E. F. Codd in 1970.
A Relational Database Management System (RDBMS) is a type of database management system that stores data in a structured for ...
s without using
locking.
There are several non-lock concurrency control methods, which involve the use of timestamps on transaction to determine transaction priority:
*
Optimistic concurrency control
Optimistic concurrency control (OCC), also known as optimistic locking, is a non-locking concurrency control method applied to transactional systems such as relational database management systems and software transactional memory. OCC assumes that ...
**
Timestamp-based concurrency control In computer science, a timestamp-based concurrency control algorithm is a optimistic concurrency control method. It is used in some databases to safely handle transactions using timestamps.
Operation
Assumptions
* Every timestamp value is unique ...
** Validation-based concurrency control
**
Multiversion concurrency control
Multiversion concurrency control (MCC or MVCC), is a non-locking concurrency control method commonly used by database management systems to provide concurrent access to the database and in programming languages to implement transactional memory.
...
***
Snapshot isolation
In databases, and transaction processing (transaction management), snapshot isolation is a guarantee that all reads made in a transaction will see a consistent snapshot of the database (in practice it reads the last committed values that existed a ...
See also
*
Concurrency pattern In software engineering, concurrency patterns are those types of design patterns that deal with the multi-threaded programming paradigm.
Examples of this class of patterns include:
* Active object
* Balking pattern
* Barrier
* Double-check ...
*
InterBase
InterBase is a relational database management system (RDBMS) currently developed and marketed by Embarcadero Technologies. It runs on the operating systems Microsoft Windows, macOS, Linux, Oracle Solaris, Solaris, Android (operating system), Andr ...
*
Lock-free and wait-free algorithms
In computer science, an algorithm is called non-blocking if failure or suspension of any thread cannot cause failure or suspension of another thread; for some operations, these algorithms provide a useful alternative to traditional blocking i ...
References
Concurrency control
Transaction processing
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