JSON Swiss

JSON Swiss

JSON To SQL Generator

JSON Input

Loading editor…

Generated SQL

Configuration

SQL Generation Options

Add primary key and NOT NULL constraints where appropriate

Add JSON data to generate SQL statements

CREATE TABLE statements with data types and constraints

How to convert JSON to SQL – step-by-step guide

Use this JSON to SQL generator to create SQL table definitions from JSON samples for relational databases and analytics pipelines.

  1. Step 1 – Paste a JSON sample

    • Paste a representative JSON object or array into the left editor.
    • Include nested objects, arrays, and nullable fields so types are inferred correctly.
    • Use Import to load JSON from a file, URL, or sample data.

  2. Step 2 – Choose SQL generation options

    • Set a root Table Name (for example root).
    • Decide how to handle nested objects (flatten columns vs store as JSON).
    • Review how arrays are mapped (join tables vs JSON columns) based on your database.

  3. Step 3 – Review the generated code

    • Check field names, types, and how arrays/objects are modeled.
    • Adjust options like Root Type Name, null handling, and frameworks if available.
    • If a field is inferred incorrectly, tweak your sample JSON and regenerate.

  4. Step 4 – Apply the SQL in your database

    • Run the generated CREATE TABLE statements in your database.
    • Insert sample rows and verify types (numeric vs text, timestamps, booleans).
    • Add indexes and constraints to match query patterns and data integrity needs.

  5. Step 5 – Copy or download

    • Copy the output into your project or download it as a file.
    • Run your formatter/linter to match your code style.
    • Add JSON parsing/serialization libraries if your language requires them.

Quick tips

  • Prefer explicit types for stability (avoid overly-generic TEXT for everything).
  • Keep a JSON column for fields that change frequently to avoid migrations.
  • Validate JSON before conversion so schema inference is consistent.
Example output (simplified)
-- JSON input
{
  "id": 123,
  "name": "Maeve Winters",
  "email": "maeve@example.com",
  "active": true,
  "roles": ["admin", "editor"],
  "metadata": { "plan": "pro" },
  "createdAt": "2024-03-01T10:15:00Z",
  "score": 99.5,
  "notes": null
}

-- Generated SQL (simplified)
CREATE TABLE root (
  id INTEGER NOT NULL,
  name TEXT NOT NULL,
  email TEXT,
  active BOOLEAN NOT NULL,
  created_at TIMESTAMP,
  score DOUBLE PRECISION,
  notes JSON
);

CREATE TABLE root_roles (
  root_id INTEGER NOT NULL,
  role TEXT NOT NULL
);

Related JSON & SQL tools

Explore more JSON and schema tools that work great alongside this JSON to SQL generator.

JSON to SQL Converter

Convert JSON into SQL-friendly formats and scripts for common databases.

JSON Schema Generator

Generate a JSON Schema to validate payloads before importing into SQL.

JSON Formatter & Validator

Format and validate JSON before generating SQL to avoid bad imports.

JSON Validator

Validate JSON syntax and structure before converting to SQL schemas.

Frequently Asked Questions

What SQL dialects are supported?

The generator supports MySQL, PostgreSQL, SQLite, and SQL Server dialects with appropriate data type mappings and syntax variations for each database system.

How are JSON data types mapped to SQL?

Numbers become INTEGER/DECIMAL, strings become VARCHAR/TEXT, booleans become BOOLEAN/INTEGER, arrays and objects are stored as JSON/TEXT depending on database support.

Can I generate CREATE TABLE statements?

Yes! The generator creates both CREATE TABLE statements based on your JSON structure and INSERT statements with your actual data values.

How does constraint generation work?

When enabled, the generator adds primary key constraints and NOT NULL constraints where appropriate based on your data structure and the selected SQL dialect.

JSON to SQL Schema Generator Online | JSONSwiss