Export Seed Data as a JSON Array

JSON Output Format

The JSON Array output format produces a structured array of objects where each object represents a database row. This is ideal for scenarios where raw SQL is not the best fit.

Single Table Output

For a single table, the output is a plain JSON array:

[
  {
    "id": 1,
    "first_name": "James",
    "last_name": "Smith",
    "email": "james.smith42@gmail.com",
    "is_active": true
  },
  {
    "id": 2,
    "first_name": "Emily",
    "last_name": "Garcia",
    "email": "emily.garcia17@outlook.com",
    "is_active": false
  }
]

Multiple Table Output

When the schema contains multiple tables, the output becomes an object keyed by table name:

{
  "users": [ ... ],
  "products": [ ... ]
}

SQL Type → JSON Type Mapping

SQL Type	JSON Type	Example
INTEGER, SERIAL	number	42
DECIMAL, FLOAT	number	19.99
VARCHAR, TEXT	string	"hello"
BOOLEAN	boolean	true
TIMESTAMP, DATE	string	"2023-07-15 14:27:38"
NULL values	null	null

Use Cases for JSON Seeds

• API Mocking: Load the JSON into a mock server (e.g., MSW, json-server) to simulate backend responses during frontend development
• Test Fixtures: Import the JSON file in your test suite as a fixture for integration and E2E tests
• ORM Seeding: Use frameworks like Prisma, Sequelize, or TypeORM that accept JSON objects for their seed scripts
• Frontend Prototyping: Feed the JSON directly into React state or a context provider for UI development

Pretty-Printed Output

The JSON output is always formatted with 2-space indentation for readability. You can minify it externally if size is a concern.