Article · Wikipedia archive · Last revised May 28, 2026

Comdb2

Comdb2 is an open source, highly available clustered RDBMS developed by Bloomberg LP, built on optimistic concurrency control techniques. It provides multiple isolation levels, including Snapshot and Serializable Isolation. Read/Write transactions run on any node, with the client library transparently negotiating connections to lowest cost (latency) node which is available. Comdb2 implements queues for publisher-to-subscriber message delivery. Queues can be combined with table triggers for time-consistent log distribution.

Last revised
May 28, 2026
Read time
≈ 1 min
Length
183 w
Citations
4
Source
Comdb2
Original authorComdb2 Team
DevelopersComdb2 team, and other open source component developers
Initial release1 January 2016 (2016-01-01)1
Stable release
7.0
Written inC
Operating systemLinux, Solaris, AIX
Available inEnglish
TypeRDBMS
LicenseApache v2, BSD License, MIT License, Sleepycat License2
Websitebloomberg.github.io/comdb2/

Comdb2 is an open source, highly available clustered RDBMS developed by Bloomberg LP, built on optimistic concurrency control techniques. It provides multiple isolation levels, including Snapshot and Serializable Isolation. Read/Write transactions run on any node, with the client library transparently negotiating connections to lowest cost (latency) node which is available. Comdb2 implements queues for publisher-to-subscriber message delivery. Queues can be combined with table triggers for time-consistent log distribution.

Comdb2 supports the SQLite dialect of SQL with some modifications,3 and embeds the Lua scripting language. Comdb2 maintains a fork of Berkeley DB to provide the key–value database backend to SQLite.

Comdb2 architecture was described in detail in this 2016 technical paper.4

See also

See also

References

References

  1. "Comdb2". Comdb2 Website. Retrieved 2020-11-18.
  2. "Comdb2 Licenses". Comdb2 Licenses.
  3. "SQL language | Comdb2 Documentation". bloomberg.github.io. Retrieved 2020-11-18.
  4. "Comdb2 - Bloomberg's Highly Available Relational Database System" (PDF). Archived from the original (PDF) on 2016-09-28.