whitedb

man(7)                          whitedb man page                          man(7)



NAME
       WhiteDB - shared memory database library

SYNOPSIS
       [see Doc folder and http://whitedb.org for the full manual]

DESCRIPTION
       WhiteDB is a lightweight NoSQL database library written in C, operating
       fully in main memory.  There is no server process. Data is read and
       written directly from/to shared memory, no sockets are used between
       WhiteDB and the application program. All the data is accessible to
       separate processes.

       Each database record is a tuple of N elements, encoded in WhiteDB-s
       simple compact format.  You can store both conventional datatypes and
       direct pointers to records: the latter enables highly efficient traversal
       of complex data.

       Each element is encoded as an integer: configurable as either 32 or 64
       bits.  The integers in the tuple encode values directly or as pointers.
       Columns have no type: any encoded value can be stored to any field.  You
       can always get a direct pointer to a record, store it into a field of a
       record or use it in your own program directly. A record pointer can thus
       be used as an automatically assigned id of the record which requires no
       search at all to access the record.

       The low bits of an integer in a record indicate the type of data.
       Anything which does not fit into the remainining bits is allocated
       separately and pointed to by the same integer.

       We use a database level lock implemented via a task-fair atomic spinlock
       queue for concurrency control, but alternative faster and simpler
       preference policies can be configured: either a reader-preference or a
       writer-preference spinlock.  We provide safe atomic updates of simple
       values without taking a write lock.

       The simplest index provided is a T-tree index on any field containing any
       mixture of objects (integers, strings, etc).  The index is automatically
       maintained when records are added, deleted or changed.

       Two mechanisms are available for storing the shared memory database to
       disk.  First, the whole database can be dumped and restored.  Second, all
       inserts, deletions and updates can be logged to a file.


SEE ALSO
       The Whitedb web site can be found at:
                     http://whitedb.org

REPORTING PROBLEMS
       Please use either https://github.com/priitj/whitedb or email to authors.

AUTHORS
       Copyright (C) 2008-2014 Tanel Tammet (tanel.tammet@gmail.com), Priit Järv
       (priit@whitedb.org)





0.7                                27 Jan 2014                            man(7)