Data Dictionary Generator

How to Use This Tool

This tool generates a data dictionary and a table relationship diagram from a JSON input that defines your database schema.

Step 1: Generate the Input JSON from Your Database

You need to query your database's metadata to get the table and column information. Here are example queries for popular databases:

PostgreSQL Query

SELECT json_build_object(
  'tables', (SELECT json_agg(...) FROM ...), 
  'relationships', (SELECT json_agg(...) FROM ...)
);
                

A full query for PostgreSQL is complex. It's often easier to use a script (Python, Node.js) with a database driver to inspect the schema and build the JSON.

MySQL Query

-- For tables and columns:
SELECT table_name, column_name, data_type, is_nullable, column_key, extra 
FROM information_schema.columns 
WHERE table_schema = 'your_database_name';

-- For relationships:
SELECT table_name, referenced_table_name, constraint_name 
FROM information_schema.referential_constraints 
WHERE constraint_schema = 'your_database_name';
                

You'll need to run these queries and manually format the results into the required JSON structure below.

Step 2: Format the JSON

The JSON must have a `tables` array and a `relationships` array. Paste the example below into the text box to see how it works.

Paste Your Schema (JSON format)