Blackhole (storage engine)
| Developer(s) | Oracle and MariaDB |
|---|---|
| Engine | |
| Operating system | Cross-platform |
| Type | Database engine |
| License | GNU General Public License |
Search Blackhole (storage engine) on Amazon.
BLACKHOLE is a storage engine for MySQL and MariaDB relational database management systems, developed by Oracle and MariaDB. It was introduced in version 5.0 of MySQL and was present in MariaDB since the beginning.
The SHOW ENGINES command describes BLACKHOLE as: /dev/null storage engine (anything you write to it disappears). It refers to /dev/null, a Linux/UNIX special device that contains no data.
This means that BLACKHOLE tables are always empty, they can have no data. When a user tries to insert a row MySQL will report success, but nothing will happen. When trying to modify or delete rows MySQL will report success, but the reported number of affected rows will always be zero. Any query will return an empty result set.
Use cases[edit]
The use cases for BLACKHOLE are:
- Logging insertions in the binary log without writing anything in the local server, so that the new rows will only be created in the replicas.
- Testing SQL statements correctness or the speed of the parsing process without modifying any data.
See also[edit]
External links[edit]
- The BLACKHOLE Storage Engine in the MySQL documentation
- BLACKHOLE in the MariaDB KnowledgeBase
This article "Blackhole (storage engine)" is from Wikipedia. The list of its authors can be seen in its historical and/or the page Edithistory:Blackhole (storage engine). Articles copied from Draft Namespace on Wikipedia could be seen on the Draft Namespace of Wikipedia and not main one.
