wxSQLite3 component info
------------------------

Website:      http://wxcode.sourceforge.net/components/wxsqlite3
Version:      1.7.2
Description:
wxSQLite3 is a C++ wrapper around the public domain SQLite 3.x database
and is specifically designed for use in programs based on the wxWidgets
library.

wxSQLite3 does not try to hide the underlying database, in contrary
almost all special features of the current SQLite3 version 3.3.10 are
supported, like for example the creation of user defined scalar or
aggregate functions.

Since SQLite stores strings in UTF-8 encoding, the wxSQLite3 methods
provide automatic conversion between wxStrings and UTF-8 strings. This
works best for the Unicode builds of wxWidgets. In ANSI builds the
current locale conversion object (wxConvCurrent) is used for conversion
to/from UTF-8. Special care has to be taken if external administration
tools are used to modify the database contents, since not all of these
tools operate in Unicode or UTF-8 mode.


Version history
---------------

 1.7.2 - Upgrade to SQLite version 3.3.11
         Support for loadable extensions is now optional
         Check for optional wxSQLite3 features at runtime
         wxSQLite3 API independent of optional features
 1.7.1 - Fixed a bug in the key based database encryption feature
         (The call to sqlite3_rekey in wxSQLite3Database::ReKey
         could cause a program crash, when used to encrypt a previously
         unencrypted database.)
 1.7.0 - Upgrade to SQLite version 3.3.10
         Added support for BLOBs as wxMemoryBuffer objects
         Added support for loadable extensions
         Optional support for key based database encryption
 1.6.0 - Added support for user-defined collation sequences
 1.5.3 - Upgrade to SQLite version 3.3.6
         Added support for optional SQLite meta data methods
 1.5.2 - Fixed a bug in wxSQLite3Database::Prepare
         Added wxSQLite3Database::IsOpen for convenience
 1.5.1 - SQLite DLL upgraded to version 3.3.4
 1.5   - Upgrade to SQLite version 3.3.3
         Added support for commit, rollback and update callbacks
 1.4.2 - Optimized code for wxString arguments
 1.4.1 - Fixed a bug in TableExists, eliminated some compiler warnings
         Changed handling of Unicode string conversion
         Added support for different transaction types
 1.4   - Optionally load SQLite library dynamically at run time
 1.3.1 - Corrected wxSQLite3ResultSet::GetInt64,
         added wxSQLite3Table::GetInt64
 1.3   - Added wxGTK build support
 1.2   - Corrected error in wxSQLite3Table::FindColumnIndex
 1.1   - Upgrade to SQLite version 3.2.7
 1.0   - First public release


Installation
------------

a) wxMSW

When building on win32, you can use the makefiles in the BUILD folder.

SQLite version 3.3.10 DLL is included. The included link library was
built with MS Visual C++ 6. For other compilers it can be necessary to
regenerate the link library based on the sqlite.def file in the LIB
folder.

mingw: dlltool -d sqlite3.def -D sqlite3.dll -l sqlite3.a

The directory sqlite3/lib contains the original DLL from the SQLite
distribution.

The directory sqlite3/meta contains a special DLL version including
support for the optional SQLite meta data methods.

To get the sample application to work the SQLite DLL to be used has to
be copied to the samples directory.

If you want to use the optional SQLite meta data methods SQLite needs
to be compiled with SQLITE_ENABLE_COLUMN_METADATA (as is the case for
the DLL version in directory sqlite3/meta). Additionally the
preprocessor symbol WXSQLITE3_HAVE_METADATA must be defined when
compiling wxSQLite3.

b) wxGTK

When building on an autoconf-based system (like Linux/GNU-based
systems), you can use the existing configure script in the component's
ROOT folder or you can recreate the configure script doing:

  cd build
  ./acregen.sh
  cd ..

  ./configure [here you should use the same flags you used to configure wxWidgets]
  make
 
Type "./configure --help" for more info.
The autoconf-based systems also support a "make install" target which
builds the library and then copies the headers of the component to
/usr/local/include and the lib to /usr/local/lib.

SQLite version 3.3.10 is NOT included. You have to download the current
version of SQLite from http://www.sqlite.org and to install it on your
system before you can install wxSQLite3.


Optional Meta Data support
--------------------------

If you want to use the optional SQLite meta data methods SQLite needs
to be compiled with SQLITE_ENABLE_COLUMN_METADATA. Additionally the
preprocessor symbol WXSQLITE3_HAVE_METADATA must be defined when
compiling wxSQLite3.

For wxMSW the directory sqlite3/meta contains a special DLL version
including support for the optional SQLite meta data methods.


Optional key based database encryption support
----------------------------------------------

The public release of SQLite contains hooks for key based database
encryption, but the code for implementing this feature is not freely
available. D. Richard Hipp offers a commercial solution
(see http://www.hwaci.com/sw/sqlite/prosupport.html#crypto).

If you want to use the optional SQLite key based database encryption
you need to have the implementation of this feature and you have to
compile SQLite with the option SQLITE_HAS_CODEC. 

Additionally the preprocessor symbol WXSQLITE3_HAVE_CODEC must be
defined when compiling wxSQLite3.

There exist other commercial solutions, among them:

http://www.sqlcrypt.com
http://www.sqlite-crypt.com

Both use a slightly different encryption API, which is currently NOT
supported by wxSQLite3.

For Windows based systems there exists an open source solution:
System.Data.SQLite (see http://sqlite.phxsoftware.com). Encrypted
database files can be shared across Windows platforms only.

The author of wxSQLite3 has created a key based AES database encryption
implementation for SQLite such that sharing encrypted database files
across different platforms is supported. The implementation is based on
knowledge gained from implementing encryption support for the wxCode
component wxPdfDocument and from inspecting the source code of
System.Data.SQLite. The code implementing this feature is available in
directory sqlite3/secure/src. You may use this code on your own risk.
The subdirectory codec contains the necessary source files; copy the
complete subdirectory to the location where the source code of SQLite
resides on your system. The subdirectory pager contains modified
versions of the source file pager.c using the naming scheme pager-x.y.z,
where x.y.z is the corresponding SQLite version: replace the file
pager.c in the SQLite source directory on your system by the appropriate
version. Add the sources in subdirectory codec to the SQLite makefile
and compile SQLite with option SQLITE_HAS_CODEC enabled.

For wxMSW the directory sqlite3/secure contains a special DLL version
including support for the optional SQLite meta data methods and the
optional key based database encryption.


Using statically linked SQLite library on Windows
-------------------------------------------------

If you want or need to compile wxSQLite3 lib in such a way that it
does not require the sqlite3.dll at run-time, you have to build a
static sqlite3 library. No modifications to wxSQLite3 are required. 

The following steps are required:

- You have to download the complete source code for sqlite from
  http://www.sqlite.org/download.html. Look for the ZIP archive since
  it already includes all generated sources and is ready to compile on
  Windows without the need for additional tools.
- Unfortunately no makefile is included. That is, you have to create a
  makefile or project file yourself. You have to build a static library
  from all C source files except shell.c (which is the stand alone tool
  for sqlite3) and tclsqlite.c (which is the tcl wrapper).
- Replace the file sqlite3.lib in the wxSQLite3 distribution by the
  sqlite3.lib created as stated above and compile wxSQLite3 as a static
  library.
- Don't forget to set USE_DYNAMIC_SQLITE3_LOAD=0. 


Known bugs
----------

None


Authors' info
-------------

Ulrich Telle   utelle@users.sourceforge.net

