SQLite3 Schema Crawler

Generate a GraphViz dot file given a SQLite3 schema.

Table of Contents

• Requirements
• Installation
• Usage
• Example

Requirements

• Python 3.8 or newer

Installation

Clone this repository using:

git clone https://github.com/jlegare/SQLite3-schema-crawler.git

Usage

To generate a GraphViz drawing for a SQLite3 database, provide the path to the database file on the command-line:

python schema-crawler.py some-database.sqlite3

By default, all tables in the database will be included. This can be controlled using a combination of four options:

• --include,
• --prefix-include,
• --exclude, and
• --prefix-exclude.

Each of these options takes a single argument, but each option can be specified multiple times, their values are collected and considered as a whole. There is, however, an order of precedence to their application, namely, the order given above:

• if --include is specified, the output will contain only the specified table, otherwise
• if --prefix-include is specified, the output will contain tables whose name begins with the specified prefix, otherwise
• if --exclude is specified, the output will not contain the specified table, otherwise
• if --prefix-exclude is specified, the output will not contain tables whose name begins with the specified prefix, otherwise
• the output will contain every table encountered in the database.

For example, if db.sqlite3 is a typical Django SQLite3 database, we can consider only the migrations table using

python schema-crawler.py db.sqlite3 --include django_migrations

or all the Django-specific tables using

python schema-crawler.py db.sqlite3 --prefix-include django_

Similarly, we can consider the complementary set of tables (i.e., all tables except django_migrations or all tables except the Django-specific tables) using the --exclude and prefix-exclude options instead.

Example

If db.sqlite3 is the database generated by a plain Django project with user authentication included, but no user-defined models, then

python schema-crawler.py db.sqlite3

will generate (on stdout) a .dot file that, when run through GraphViz (with appropriate options) will yield the following diagram: