From Fedora Project Wiki
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** '''Latest release:''' 1.4.48 / 2012-08-18
 
** '''Latest release:''' 1.4.48 / 2012-08-18
 
** '''License:''' [https://www.gnu.org/licenses/lgpl.html GNU LGPL]
 
** '''License:''' [https://www.gnu.org/licenses/lgpl.html GNU LGPL]
** '''Search key length:'''
+
** '''Search key length:''' No limit apart from the data type used for holding the key and data lengths (int).
** '''Read-only access to DB:'''
+
** '''Read-only access to DB:''' Multiple processes can read a single database. Exclusion control is managed by a reader/writer lock.
 
** '''Supported architectures:''' Linux 2.4 and later (x86-32/x86-64/PowerPC/Alpha/SPARC)
 
** '''Supported architectures:''' Linux 2.4 and later (x86-32/x86-64/PowerPC/Alpha/SPARC)
** '''Query keys larger than X:'''
+
** '''Query keys larger than X:''' It is possible to access each record with the cursor in ascending or descending order. According to this mechanism, forward matching search for strings and range search for integers are realized.
  
 
* '''[http://fallabs.com/qdbm/spex.html QDBM]'''
 
* '''[http://fallabs.com/qdbm/spex.html QDBM]'''
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** '''Latest release:''' 1.8.78 / 2007-03-07
 
** '''Latest release:''' 1.8.78 / 2007-03-07
 
** '''License:''' [https://www.gnu.org/licenses/lgpl.html GNU LGPL]
 
** '''License:''' [https://www.gnu.org/licenses/lgpl.html GNU LGPL]
** '''Search key length:'''
+
** '''Search key length:''' No limit apart from the data type used for holding the key and data lengths (int).
** '''Read-only access to DB:'''
+
** '''Read-only access to DB:''' Multiple processes can read a single database. Exclusion control is managed by a reader/writer lock.
 
** '''Supported architectures:''' Linux (2.2, 2.4, 2.6) (IA32, IA64, AMD64, PA-RISC, Alpha, PowerPC, M68000, ARM)
 
** '''Supported architectures:''' Linux (2.2, 2.4, 2.6) (IA32, IA64, AMD64, PA-RISC, Alpha, PowerPC, M68000, ARM)
** '''Query keys larger than X:'''
+
** '''Query keys larger than X:''' It is possible to access each record with the cursor in ascending or descending order. According to this mechanism, forward matching search for strings and range search for integers are realized.
  
 
* '''GDBM'''
 
* '''GDBM'''

Revision as of 06:39, 28 July 2016

  • LMDB
    • Written in: C
    • Wrappers for: C++, Java, Python, Perl, Ruby, Go, Erlang, PHP, Lua
    • Packages available for: Fedora 23+, EPEL6+
    • Latest release: 0.9.18 / 2016-02-05
    • License: OpenLDAP Public License
    • Search key length: Maximum length of 1/3 of a page (~1365B)
    • Read-only access to DB: The library is fully thread-aware and supports concurrent read/write access from multiple processes and threads. (docs)
    • Supported architectures: i386/x86-64/PowerPC/ARM
    • Query keys larger than X: Using cursors: MDB_SET_RANGE - Position at first key greater than or equal to specified key.
  • Kyoto Cabinet (replacing Tokyo Cabinet)
    • Written in: C++
    • Wrappers for: C, Java, Python, Ruby, Perl, and Lua
    • Packages available for: Fedora 23+, EPEL5+
    • Latest release: 1.2.76 / 2012-05-24
    • License: GNU GPL
    • Search key length: No limit from database itself (uses c++ std::string or combination of c-style string and its length).
    • Read-only access to DB: See http://fallabs.com/kyotocabinet/spex.html, part Sharing One database by Multiple Processes. TL;DR: One DB cannot be accessed by multiple processes, DB file is protected by reader-writer lock (which means it will probably require write access even for read-only operation).
    • Supported architectures: Linux 2.6 and later (i386/x86-64/PowerPC/Alpha/SPARC)
    • Query keys larger than X: DB supports matching by regex, which should be possible to use for this kind of query. Other possibilities are match by prefix and match by similarity.
  • LevelDB
    • Written in: C++
    • Wrappers for: Java, Go, Erlang, node.js
    • Packages available for: Fedora 23+, EPEL6+
    • Latest release: 1.18 / 2014-09-16
    • License: 3-Clause BSD
    • Search key length: No limit apart from the data type used for holding the key length (size_t)
    • Read-only access to DB: A database may only be opened by one process at a time. The leveldb implementation acquires a lock from the operating system to prevent misuse. Within a single process, the same leveldb::DB object may be safely shared by multiple concurrent threads. (docs)
    • Supported architectures: i386/x86-64/PowerPC/ARM
    • Query keys larger than X: Native library's Iterator can Seek (Position at the first key in the source that at or past target) + reverse, node.js wrapper is able to use basic filters (greater than, lower than)
  • RocksDB (Built on LevelDB)
    • Written in: C++
    • Wrappers for: Java (In development)
    • Packages available for: Not yet available in Fedora
    • Latest release: 4.9.0 / 2016-06-09
    • License: 3-Clause BSD
    • Search key length: No limit apart from the data type used for holding the key length (size_t)
    • Read-only access to DB: A database may only be opened by one process at a time. The rocksdb implementation acquires a lock from the operating system to prevent misuse. Within a single process, the same rocksdb::DB object may be safely shared by multiple concurrent threads. (docs)
    • Supported architectures: x86-64/PowerPC/ARM
    • Query keys larger than X: Iterator can Seek (Position at the first key in the source that at or past target) + reverse
  • UnQlite
    • Written in: C
    • Wrappers for:
    • Packages available for: Not yet available in Fedora
    • Latest release: 1.1.6 / 2015-08-26
    • License: 2-Clause BSD
    • Search key length: No limit apart from the data type used for holding the key length (int). Data length limited by the data type unqlite_int64 (64b int).
    • Read-only access to DB: Supports concurrent readers. In order to be thread-safe, UnQLite must be compiled with the UNQLITE_ENABLE_THREADS directive defined.
    • Supported architectures:
    • Query keys larger than X: UNQLITE_CURSOR_MATCH_LE and UNQLITE_CURSOR_MATCH_GE when using cursors. This options have sense only if the underlying key/value storage subsystem support range search (i.e: B+Tree, R+Tree, etc.).

Older (probably unmantained) projects

  • TokyoCabinet (replacing QDBM)
    • Written in: C
    • Wrappers for: Perl, Ruby, Java, and Lua
    • Packages available for: Fedora 23+, EPEL5+, RHEL6+
    • Latest release: 1.4.48 / 2012-08-18
    • License: GNU LGPL
    • Search key length: No limit apart from the data type used for holding the key and data lengths (int).
    • Read-only access to DB: Multiple processes can read a single database. Exclusion control is managed by a reader/writer lock.
    • Supported architectures: Linux 2.4 and later (x86-32/x86-64/PowerPC/Alpha/SPARC)
    • Query keys larger than X: It is possible to access each record with the cursor in ascending or descending order. According to this mechanism, forward matching search for strings and range search for integers are realized.
  • QDBM
    • Written in: C
    • Wrappers for: C++, Java, Perl, and Ruby
    • Packages available for: Fedora 23+
    • Latest release: 1.8.78 / 2007-03-07
    • License: GNU LGPL
    • Search key length: No limit apart from the data type used for holding the key and data lengths (int).
    • Read-only access to DB: Multiple processes can read a single database. Exclusion control is managed by a reader/writer lock.
    • Supported architectures: Linux (2.2, 2.4, 2.6) (IA32, IA64, AMD64, PA-RISC, Alpha, PowerPC, M68000, ARM)
    • Query keys larger than X: It is possible to access each record with the cursor in ascending or descending order. According to this mechanism, forward matching search for strings and range search for integers are realized.
  • GDBM
    • Written in:
    • Wrappers for:
    • Packages available for:
    • Latest release:
    • License:
    • Search key length:
    • Read-only access to DB:
    • Supported architectures:
    • Query keys larger than X:
  • NDBM
    • Written in:
    • Wrappers for:
    • Packages available for:
    • Latest release:
    • License:
    • Search key length:
    • Read-only access to DB:
    • Supported architectures:
    • Query keys larger than X: