BF-SQLite: SQLite File-Format Access in BrainFuck

BF-SQLite is an experimental project designed to interface with SQLite databases using the BrainFuck programming language, employing only standard Linux primitives. This initiative highlights how software typically deemed complex can be constructed quickly with the assistance of AI. Inspired by Matt Shumer's article Something Big is Happening, the project illustrates the capabilities of BrainFuck rather than advocating for its practical application in database operations.

Key Features

• Header Parsing: Read and validate the SQLite header.
• Schema Walking: Navigate through schema pages with ease.
• Table Scanning: Perform a thorough scan of tables, allowing insights into the data structure.
• Column Projection: Limited SQL-style projections are supported, for example:

SELECT name FROM users;  
SELECT name, sex FROM users;  

• Table Creation: Execute commands to create new demo tables:

CREATE TABLE log (ts INT, value TEXT);  

• Data Manipulation: Conduct basic INSERT, UPDATE, and DELETE operations on a minimal demo database.

Current Capabilities

The following functionalities have been successfully implemented:

• Reading and validating headers
• Performing page reads
• Walking through schemas
• Scanning demo tables
• Executing simple SELECT queries on the demo users table
• Creating a narrow demo table with basic structure
• Conducting small controlled write operations

Operational Overview

The interaction model operates as follows:

SQLite .db file
       ↑
       │ dd / raw page bytes
       │
Shell pager
       ↑
       │ ASCII request/response
       │
BrainFuck program

The protocol is intentionally designed to be straightforward:

• H reads the 100-byte SQLite header and displays it in hexadecimal format.
• R <page_size> <page_no> retrieves a page and returns it as hex.
• W <page_size> <page_no> writes a specified page back in hexadecimal format.

Project Structure

The repository is organized into distinct directories for clarity and efficiency:

• bf/ - Contains demo programs and BrainFuck helper libraries.
• examples/ - Hosts curated demos and reference sketches.
• scripts/ - Includes pagination, build, and execution helpers.
• tools/ - Offers a Dockerized toolchain.
• docs/archive/ - Contains older planning and maintenance notes.

Scope

BF-SQLite serves specifically as a BrainFuck-driven SQLite file-format demonstration and is not intended to function as a full SQLite replacement or SQL engine.