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upscaledb 2.2.1                                   Fr 10. Mär 21:33:03 CET 2017
(C) Christoph Rupp, chris@crupp.de; http://www.upscaledb.com

This is the README file of upscaledb.

Contents:

1. About

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

This release has a bunch of bug fixes, performance improvements and a new
API for bulk operations.

2. Changes

New Features
* Added a new API function for bulk operations (ups_db_bulk_operations in
	ups/upscaledb_int.h)

Bugfixes
* Fixed compiler error related to inline assembly on gcc 4.8.x
* Fixed bug when ups_cursor_overwrite would overwrite a transactional record
	instead of the (correct) btree record
* Fixed several bugs in the duplicate key consolidation
* issue #80: fixed streamvbyte compilation for c++11
* issue #79: fixed crc32 failure when reusing deleted blobs spanning
	multiple pages
* Fixed a bug when recovering duplicates that were inserted with one of the
	UPS_DUPLICATE_INSERT_* flags
* Minor improvements for the journalling performance
* Fixed compilation issues w/ gcc 6.2.1 (Thanks, Roel Brook)

Other Changes
* Performance improvements when appending keys at the end of the database
* The flags UPS_HINT_APPEND and UPS_HINT_PREPEND are now deprecated
* Removed the libuv dependency; switched to boost::asio instead
* Performance improvements when using many duplicate keys (with a
	duplicate table spanning multiple pages)
* Committed transactions are now batched before they are flushed to disk
* The integer compression codecs UPS_COMPRESSOR_UINT32_GROUPVARINT and
	UPS_COMPRESSOR_UINT32_STREAMVBYTE are now deprecated
* The integer compression codec UPS_COMPRESSOR_UINT32_MASKEDVBYTE is now a
	synonym for UPS_COMPRESSOR_UINT32_VARBYTE, but uses the MaskedVbyte
	library under the hood.
* Added Mingw compiler support (thanks, topilski)

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

3. Features

- 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
- Transparent AES encryption
- Transparent CRC32 verification
- Various compression codecs for journal, keys and records using 
    zlib, snappy, lzf
- Compression for uint32 keys
- 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 the APL 2.0 license
- Wrappers for C++, Java, .NET, Erlang, Python, Ada and others

4. Known Issues/Bugs

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

5. Compiling

5.1 Linux, MacOS and other Unix systems

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

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

5.2 Microsoft Visual Studio

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

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

5.3 Dependencies

On Ubuntu, the following packages are required:
  - libdb-dev (optional)
  - protobuf-compiler
  - libprotobuf-dev
  - libgoogle-perftools-dev
  - libboost-system-dev
  - libboost-filesystem-dev
  - libboost-thread-dev
  - libboost-dev

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

6. Testing and Example Code

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

7. API Documentation

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

8. Porting upscaledb

Porting upscaledb shouldn't be too difficult. All operating
system dependend functions are declared in '1os/*.h' and defined
in '1os/os_win32.cc' or '1os/os_posix.cc'.
Other compiler- and OS-specific macros are in 'include/ups/types.h'.
Most likely, these are the only files which have to be touched. Also see item
9) for important macros.

9. Migrating files from older versions

Usually, upscaledb 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 ups_export linked against the old version.
(ups_export links statically and will NOT be confused if your system has a
newer version of upscaledb installed). Then use the newest version of
ups_import to import the data into a new database. You can find ups_export
and ups_import in the "tools" subdirectory.

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

    ups_export-2.1.2 input.db | ups_import --stdin output.db

10. Licensing

upscaledb is released under the Apache Public License (APL) 2.0. See the
file COPYING for more information.

For commercial use licenses are available. Visit http://upscaledb.com
for more information.

11. Contact

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

12. 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.