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<title>The SQLite Amalgamation</title>
<tcl>hd_keywords {amalgamation} {the amalgamation}</tcl>

<h2>The SQLite Amalgamation</h2>

<p>The core SQLite library consists of about 96 files of C code
(as of [Version 3.6.21]) in the core with 11 additional files
in the [FTS3] and [RTREE] extensions.
Most of these are "source" files in the sense that they are stored 
in the configuration management system and are maintained directly. 
But 6 of the core C files are generated automatically during the 
compilation process.  Of the 96 code files, 76 are C code and 
20 are C header files.</p>

<p>The standard makefiles for SQLite have a target for building
an object we call the "amalgamation".  
The amalgamation is a single C code file, named "sqlite3.c",
that contains all C code 
for the core SQLite library and the [FTS3] and [RTREE] extensions.
This file contains about 110K lines of code 
(65K if you omit blank lines and comments) and is over 3.8 megabytes
in size.</p>

<p>The amalgamation contains everything you need to integrate SQLite 
into a larger project.  Just copy the amalgamation into your source 
directory and compile it along with the other C code files in your project.
You may also want to make use of the "sqlite3.h" header file that 
defines the programming API for SQLite. 
The sqlite3.h header file is available separately. 
The sqlite3.h file is also contained within the amalgamation, in
the first couple of thousand lines. So if you have a copy of 
sqlite3.c but cannot seem to locate sqlite3.h, you can always 
regenerate the sqlite3.h by copying and pasting from the amalgamation.</p>

<p>In addition to making SQLite easier to incorporate into other
projects, the amalgamation also makes it run faster. Many
compilers are able to do additional optimizations on code when 
it is contained with in a single translation unit such as it 
is in the amalgamation. We have measured performance improvements
of between 5 and 10% when we use the amalgamation to compile 
SQLite rather than individual source files.  The downside of this
is that the additional optimizations often take the form of 
function inlining which tends to make the size of the resulting
binary image larger.</p>

<p>The amalgamation and
the sqlite3.h header file are available on
the <a href="download.html">download page</a> as a file 
where the X is replaced by the appropriate version number.</p>