In
computer programming
Computer programming or coding is the composition of sequences of instructions, called computer program, programs, that computers can follow to perform tasks. It involves designing and implementing algorithms, step-by-step specifications of proc ...
, Database-as-
IPC may be considered an
anti-pattern
An anti-pattern in software engineering, project management, and business processes is a common response to a recurring problem that is usually ineffective and risks being highly counterproductive. The term, coined in 1995 by computer programmer An ...
where a disk persisted table in a database is used as the message queue store for routine
inter-process communication
In computer science, interprocess communication (IPC) is the sharing of data between running Process (computing), processes in a computer system. Mechanisms for IPC may be provided by an operating system. Applications which use IPC are often cat ...
(IPC) or subscribed data processing. If database performance is of concern, alternatives include
sockets,
network socket
A network socket is a software structure within a network node of a computer network that serves as an endpoint for sending and receiving data across the network. The structure and properties of a socket are defined by an application programming ...
, or
message queue
In computer science, message queues and mailboxes are software-engineering components typically used for inter-process communication (IPC), or for inter- thread communication within the same process. They use a queue for messaging – the ...
.
British
computer scientist
A computer scientist is a scientist who specializes in the academic study of computer science.
Computer scientists typically work on the theoretical side of computation. Although computer scientists can also focus their work and research on ...
, Junade Ali, defined the Database-as-IPC Anti-Pattern as using a database to "schedule jobs or queue up tasks to be completed", noting that this anti-pattern centres around using a database for temporary messages instead of persistent data.
Controversy
The issue arises if there is a performance issue, and if additional systems (and servers) can be justified. In terms of performance, recent advancements in database systems provide more efficient mechanisms for signaling and messaging, and database systems also support memory (non-persisted) tables.
There are databases with built-in notification mechanisms, such as PostgreSQL, SQL Server, and Oracle. These mechanisms and future improvements of database systems can make queuing much more efficient and avoid the need to set up a separate signaling or messaging queue system along with the server and management overhead.
While MySQL doesn't have direct support for notifications, some workarounds are possible. However, they would be seen as non-standard and therefore more difficult to maintain.
5 subtle ways you’re using MySQL as a queue, and why it’ll bite you
Schwartz, Baron. 2011 September 14.
See also
* Inbox and outbox pattern
{{Orphan, date=April 2023
The inbox pattern and outbox pattern are two related patterns used by applications to persist data (usually in a database) to be used for operations with guaranteed delivery. The inbox and outbox concepts are used in the ...
References
Anti-patterns
Databases
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