SQLite is a self-contained, high-reliability, embedded, full-featured, public-domain, SQL database engine. SQLite is the most used database engine in the world. It can be used to store and maintain eBooks.
- Transactions are atomic, consistent, isolated, and durable (ACID) even after system crashes and power failures.
- Zero-configuration - no setup or administration needed.
- Full-featured SQL implementation with advanced capabilities like partial indexes, indexes on expressions, JSON, and common table expressions.
- A complete database is stored in a single cross-platform disk file. Great for use as an application file format.
- Supports terabyte-sized databases and gigabyte-sized strings and blobs. (See limits.html.)
- Small code footprint: less than 500KiB fully configured or much less with optional features omitted.
- Simple, easy to use API.
- Written in ANSI-C. TCL bindings included. Bindings for dozens of other languages available separately.
- Well-commented source code with 100% branch test coverage.
- Available as a single ANSI-C source-code file that is easy to compile and hence is easy to add into a larger project.
- Self-contained: no external dependencies.
- Cross-platform: Android, *BSD, iOS, Linux, Mac, Solaris, VxWorks, and Windows (Win32, WinCE, WinRT) are supported out of the box. Easy to port to other systems.
- Sources are in the public domain. Use for any purpose.
- Comes with a standalone command-line interface (CLI) client that can be used to administer SQLite databases.
- The SQLite library is designed to be very easy to use from a Tcl or Tcl/Tk script. SQLite began as a Tcl extension and the primary test suite for SQLite is written in TCL. SQLite can be used with any programming language, but its connections to TCL run deep.
 Uses in eBooks
- kepub uses a SQL database to manage eBooks
- KPF file format, which is KFX data stored in a SQL database. New KFX dictionaries are stored in this format.
 For more information
- SQL tutorial at W3Schools