[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Wb-discuss] wb-2b4 available

From: Aubrey Jaffer
Subject: [Wb-discuss] wb-2b4 available
Date: Mon, 17 Feb 2020 12:17:32 -0500

This message announces the availability of wb-2b4.

"WB" is a disk based (sorted) associative-array database package
providing C, SCM, Java, and C# libraries.  These associative arrays
consist of variable length (0.B to 255.B) keys and values.  Functions
are provided to:

   * create, destroy, open and close disk-files and associative arrays;

   * insert, delete, retrieve, find next, and find previous (with
     respect to dictionary order of keys); and

   * apply functions, delete, or modify values over a range of
     consecutive key values.

WB is thread safe (so long as HAND structures are not shared between
threads).  The `put' and `rem' operations allow associations to be
used for thread mutexs.

The WB implementation has a file size limit of 2^32 * block size
(default 2048.B) = 2^43 bytes (8796.GB).  WB does its own memory and
disk management and maintains a RAM cache of recently used blocks.
Multiple associative arrays can reside in one disk file.  Simultaneous
access to multiple disk files is supported.

The (database) disk files interoperate between the various language
platforms.  The interface to the SCM Scheme implementation supports
longer data values and SLIB relational databases.

A structure checking and garbage collecting program and a block viewer
are provided.

WB is lightweight; compiled on x86_64 GNU/Linux, the wb-2b4 library
sizes are:

  java/wb.jar    51 kB  Java archive (zipped)
  csharp/Wb.dll  63 kB  PE for MS Windows (DLL) Mono/.Net assembly
  c/libwb.so     81 kB  ELF 64-bit LSB shared object, stripped
                 91 kB  ELF 64-bit LSB shared object, not stripped
  c/libwb.a     131 kB  binary 64-bit library archive
  c/wbscm.so    113 kB  ELF 64-bit LSB shared object DLL for SCM, not stripped

WB is implemented using a variant of B-tree structure.  B-trees give
slower access than hashing but are dynamic and provide an efficient
determination of successor and predecessor keys.  All operations are
O(log(n)) in the size of the database.  B-trees are commonly used by
database systems for implementing index structures.  B-trees are
optimized for using the minimum number of disk operations for large data
structures.  Prefix and suffix key compression are used for storage
efficiency in WB.

WB is free software and part of the GNU project.  It is released under
the GNU Lesser General Public License (LGPL).

Documentation and distributions in several formats are linked from
WB's home page:


Links to distributions of WB and related softwares are at the end of
this message.

wb-2b4 news:

wb-2b4 is a maintenance release to parallel scm.  Details at

 from Manfred Winterhoff
        * c/db.c (create_db, open_db): sizeof --> strlen.


WB source is available from:
Also available as a binary RPM:

WB comes with an interface to the Scheme implementation SCM; and
contains "wbtab.scm", SCM code allowing WB to implement SLIB
relational databases.

SCM source is available from:
Also available as a binary RPMs:
The i386 MS-Windows installer for SCM includes the WB Scheme API:

SLIB is a portable Scheme library which SCM uses:
Also available as RPM:
Also available as MS-Windows installer:

reply via email to

[Prev in Thread] Current Thread [Next in Thread]