Comprehensive Guide & Reference: SQL to JSON & Relational Data Migration
Translating relational database tables (SQL) into document-oriented schemas (JSON) is a core step when migrating legacy MySQL or PostgreSQL databases to MongoDB, Firebase, or REST APIs.
1. Type Mapping Between SQL & JSON
| SQL Relational Type | JSON Data Type | Example Conversion |
|---|---|---|
| VARCHAR / TEXT | string | 'Alice' → "Alice" |
| INT / FLOAT / NUMERIC | number | 42, 19.99 → 42, 19.99 |
| BOOLEAN / TINYINT(1) | boolean | TRUE / FALSE → true / false |
| NULL | null | NULL → null |
2. Common Migration Use Cases
- Database Seeding: Convert JSON mock data generated by LLMs or Faker.js directly into SQL
INSERTstatements to populate local test databases. - API Payload Mocking: Export production SQL table dumps into JSON fixtures for unit tests and frontend mocking in Cypress or Jest.
- NoSQL Document Migration: Transform SQL table exports into document collections for ingestion into MongoDB or AWS DynamoDB.