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hamsterdb 2.1.11                                   Mi 6. Mai 09:40:22 CEST 2015
(C) Christoph Rupp, chris@crupp.de; http://www.hamsterdb.com

This is the README file of hamsterdb.

Contents:

1. About

hamsterdb is a database engine written in C/C++. It is fast, production-proven
and easy to use.

This release has several bug fixes (see below for a list). One bug is a race
condition on Win32 which can lead to application crashes. The other bugs can
lead to wrong query results if Transactions are enabled and approximate
matching is used.

In addition, there were minor performance improvements.

The file format is compatible to 2.1.10.

2. Changes

New Features
* none

Bugfixes
* C++ API no longer throws exceptions in destructors (thanks, Michael Möllney)
* issue #49: fixed approx. matching issue with remote server
* issue #53: fixed race condition on Win32
* issue #52: fixed cursor iteration w/ txns and approx matching
* issue #50: removing problematic debug checks

Other Changes
* Reducing I/O operations by allocating large buffers if file grows fast
* Add InsertRecNo method to hamsterdb-dotnet (thanks, mjmckp)

To see a list of all changes, look in the file ChangeLog.

3. Roadmap
- See https://github.com/cruppstahl/hamsterdb/wiki/Roadmap

4. Features

- PRO: SIMD instructions for lookups
- PRO: transparent AES encryption
- PRO: transparent CRC32 verification
- PRO: transparent compression for journal, keys and records using 
    zlib, snappy, lzf or lzo
- PRO: compression for uint32 keys

- Very fast sorted B+Tree with variable length keys
- Basic schema support for POD types (i.e. uint32, uint64, real32 etc)
- Very fast analytical functions
- Can run as an in-memory database
- Multiple databases in one file
- Record number databases ("auto-increment")
- Duplicate keys
- Logging and recovery
- Unlimited number of parallel Transactions
- Partial reading/writing of records
- Network access (remote databases) via TCP/Protocol Buffers
- Very fast bi-directional database cursors
- Configurable page size, cache size, key sizes etc
- Runs on Linux, Unices, Microsoft Windows and other architectures
- Uses memory mapped I/O for fast disk access (but falls back to read/write if
    mmap is not available)
- Uses 64bit file pointers and supports huge files (>2 GB)
- Easy to use and well-documented
- Open source and released under APL 2.0 license
- Wrappers for C++, Java, .NET, Erlang, Python, Ada and others

5. Known Issues/Bugs

See https://github.com/cruppstahl/hamsterdb/issues.

6. Compiling

6.1 Linux, MacOS and other Unix systems

To compile hamsterdb, run ./configure, make, make install.

Run `./configure --help' for more options (i.e. static/dynamic library,
build with debugging symbols etc).

6.2 Microsoft Visual Studio

A Solution file is provided for Microsoft Visual C++ in the "win32" folder
for MSVC 2010 and MSVC 2013.
All libraries can be downloaded precompiled from the hamsterdb webpage.

To download Microsoft Visual Studio Express Edition for free, go to
http://msdn.microsoft.com/vstudio/express/visualc/default.aspx.

6.3 Dependencies

On Ubuntu, the following packages are required:
  - libdb-dev (optional)
  - protobuf-compiler
  - libprotobuf-dev
  - libgoogle-perftools-dev
  - libboost-system-dev
  - libboost-thread-dev
  - libboost-dev
  - (libuv needs to be installed from sources - see
      https://github.com/joyent/libuv)

For Windows, precompiled dependencies are available here:
https://github.com/cruppstahl/hamsterdb-alien

7. Testing and Example Code

Make automatically compiles several example programs in the directory
'samples'. To see hamsterdb in action, just run 'samples/db1'
or any other sample. (or 'win32/out/samples/db1/db1.exe' on Windows platforms).

8. API Documentation

The header files in 'include/ham' have extensive comments. Also, a doxygen
script is available; run 'make doc' to start doxygen. The generated
documentation is also available on the hamsterdb web page.

9. Other Ways to Compile hamsterdb

If you want to compile hamsterdb without using the provided ./configure
environment, you have to set some preprocessor macros:

DEBUG                   enable debugging output and diagnostic checks (slow!)
HAM_32BIT               compile for 32bit (alias: WIN32)
HAM_64BIT               compile for 64bit (alias: WIN64, also needs WIN32)

Also, if you compile for windows, you have to compile the file
'src/os_win32.cc' and ignore the file 'src/os_posix.cc'. Vice versa on
non-Windows platforms.

10. Porting hamsterdb

Porting hamsterdb shouldn't be too difficult. All operating
system dependend functions are declared in 'src/os.h' and defined
in 'src/os_win32.cc' or 'src/os_posix.cc'.
Other compiler- and OS-specific macros are in 'include/ham/types.h'.
Most likely, these are the only files which have to be touched. Also see item
9) for important macros.

11. Migrating files from older versions

Usually, hamsterdb releases are backwards compatible. There are some exceptions,
though. In this case tools are provided to migrate the database. First, export
your existing database with ham_export linked against the old version.
(ham_export links statically and will NOT be confused if your system has a
newer version of hamsterdb installed). Then use the newest version of
ham_import to import the data into a new database. You can find ham_export
and ham_import in the "tools" subdirectory.

    Example (ham_export of 2.1.2 was renamed to ham_export-2.1.2 for clarity):

    ham_export-2.1.2 input.db | ham_import --stdin output.db

12. Licensing

hamsterdb is released under the APL 2.0 license, which allows
unrestricted use for commercial and non-commercial applications. See the
file COPYING for more information.

A commercial, closed source version hamsterdb pro with additional functionality
is available on request. See http://hamsterdb.com for more information.

13. Contact

Author of hamsterdb is
    Christoph Rupp
    Paul-Preuss-Str. 63
    80995 Muenchen/Germany
    email: chris@crupp.de
    web: http://www.hamsterdb.com

14. Other Copyrights

The Google Protocol Buffers ("protobuf") library is Copyright 2008, Google Inc.
It has the following license:

    Copyright 2008, Google Inc.
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:

    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above
      copyright notice, this list of conditions and the following disclaimer
      in the documentation and/or other materials provided with the
      distribution.
    * Neither the name of Google Inc. nor the names of its
      contributors may be used to endorse or promote products derived from
      this software without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    Code generated by the Protocol Buffer compiler is owned by the owner
    of the input file used when generating it.  This code is not
    standalone and requires a support library to be linked with it.  This
    support library is itself covered by the above license.

The libuv library is part of the Node project: http://nodejs.org/
libuv may be distributed alone under Node's license:

    Copyright Joyent, Inc. and other Node contributors. All rights reserved.
    Permission is hereby granted, free of charge, to any person obtaining a copy
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    The above copyright notice and this permission notice shall be included in
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    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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