SQLite
An Embeddable SQL Database Engine

This page was last modified on 2004/04/23 17:04:45 UTC
The latest SQLite version is 2.8.17 created on 1.220.2.2 2005/06/06 UTC

Introduction

SQLite is a C library that implements an embeddable SQL database engine. Programs that link with the SQLite library can have SQL database access without running a separate RDBMS process. The distribution comes with a standalone command-line access program (sqlite) that can be used to administer an SQLite database and which serves as an example of how to use the SQLite library.

SQLite is not a client library used to connect to a big database server. SQLite is the server. The SQLite library reads and writes directly to and from the database files on disk.

Features

• Implements most of SQL92. (Features not supported)
• A complete database (with multiple tables and indices) is stored in a single disk file.
• ACID (Atomic, Consistent, Isolated, Durable) transactions.
• Database files can be freely shared between machines with different byte orders.
• Supports databases up to 2 terabytes (2^41 bytes) in size.
• A zero-configuration database engine - no DBA needed.
• Small memory footprint: less than 30K lines of C code.
• Two times faster than PostgreSQL and MySQL for many common operations.
• Very simple C/C++ interface requires the use of only three functions and one opaque structure.
• TCL bindings included. Bindings for many other languages available separately.
• Simple, well-commented source code.
• Automated test suite provides over 90% code coverage.
• Self-contained: no external dependencies.
• Built and tested under Linux and Windows.
• Sources are in the public domain. Use for any purpose.

Current Status

A Change Summary is available on this website. You can also access a detailed change history, view open bugs, or report new bugs at the CVS server.

Complete source code and precompiled binaries for the latest release are available for download on this site. You can also obtain the latest changes by anonymous CVS access:

cvs -d :pserver:anonymous@www.sqlite.org:/sqlite login
cvs -d :pserver:anonymous@www.sqlite.org:/sqlite checkout sqlite

Whenever either of the first two digits in the version number for SQLite change, it means that the underlying file format has changed. Usually these changes are backwards compatible. See formatchng.html for additional information.

Documentation

The following documentation is currently available:

• A Quick Start guide to using SQLite in 5 minutes or less.
• Frequently Asked Questions are available online.
• Information on the sqlite command-line utility.
• SQLite is typeless.
• The SQL Language subset understood by SQLite.
• The C/C++ Interface.
• The NULL handling in SQLite versus other SQL database engines.
• The Tcl Binding to SQLite.
• The Architecture of the SQLite Library describes how the library is put together.
• A description of the virtual machine that SQLite uses to access the database.
• A description of the database file format used by SQLite.
• A speed comparison between SQLite, PostgreSQL, and MySQL.
• User-written documentation is available on the SQLite Wiki. Please contribute if you can.

The SQLite source code is 30% comment. These comments are another important source of information.

A mailing list has been set up for discussion of SQLite design issues or for asking questions about SQLite. To subscribe send an email to sqlite-users-subscribe@sqlite.org. If you would prefer to get digests rather than individual emails, send a message to to sqlite-users-digest-subscribe@sqlite.org. For additional information about operating and using this mailing list, send a message to sqlite-users-help@sqlite.org and instructions will be sent by to you by return email.

Professional Support and Custom Modifications

If you would like professional support for SQLite or if you want custom modifications to SQLite performed by the original author, these services are available for a modest fee. For additional information visit http://www.hwaci.com/sw/sqlite/support.html or contact:

D. Richard Hipp
Hwaci - Applied Software Research
704.948.4565
drh@hwaci.com

Building From Source

To build sqlite under Unix, just unwrap the tarball, create a separate build directory, run configure from the build directory and then type "make". For example:

$ tar xzf sqlite.tar.gz       Unpacks into directory named "sqlite" 
$ mkdir bld                   Create a separate build directory 
$ cd bld
$ ../sqlite/configure
$ make                        Builds "sqlite" and "libsqlite.a" 
$ make test                   Optional: run regression tests 

If you prefer, you can also build by making whatever modifications you desire to the file "Makefile.linux-gcc" and then executing that makefile. The latter method is used for all official development and testing of SQLite and for building the precompiled binaries found on this website. Windows binaries are generated by cross-compiling from Linux using MinGW

Related Sites

For information bindings of SQLite to other programming languages (Perl, Python, Ruby, PHP, etc.) and for a list of programs currently using SQLite, visit the Wiki documentation at:

http://www.sqlite.org/cvstrac/wiki