Chapter 1. What Is SQLite?
In the simplest terms, SQLite is a public-domain software package that provides a relational database management system, or RDBMS. Relational database systems are used to store user-defined records in large tables. In addition to data storage and management, a database engine can process complex query commands that combine data from multiple tables to generate reports and data summaries. Other popular RDBMS products include Oracle Database, IBM’s DB2, and Microsoft’s SQL Server on the commercial side, with MySQL and PostgreSQL being popular open source products.
The “Lite” in SQLite does not refer to its capabilities. Rather, SQLite is lightweight when it comes to setup complexity, administrative overhead, and resource usage. SQLite is defined by the following features:
- Serverless
SQLite does not require a separate server process or system to operate. The SQLite library accesses its storage files directly.
- Zero Configuration
No server means no setup. Creating an SQLite database instance is as easy as opening a file.
- Cross-Platform
The entire database instance resides in a single cross-platform file, requiring no administration.
- Self-Contained
A single library contains the entire database system, which integrates directly into a host application.
- Small Runtime Footprint
The default build is less than a megabyte of code and requires only a few megabytes of memory. With some adjustments, both the library size and memory use can be significantly reduced.
- Transactional
SQLite transactions are fully ACID-compliant, allowing safe access from multiple processes or threads.
- Full-Featured
SQLite supports most of the query language features found in the SQL92 (SQL2) standard.
- Highly Reliable
The SQLite development team takes code testing and verification very seriously.
Overall, SQLite provides a very functional and flexible relational database environment that consumes minimal resources and creates minimal hassle for developers and users.