Generate a Simple CREATE TABLE from JSON

From JSON to CREATE TABLE

The simplest conversion takes a flat JSON object and produces a CREATE TABLE statement. Each key becomes a column name, and the JSON value type determines the SQL data type.

Example JSON

{
  "id": 1,
  "name": "Alice",
  "email": "alice@example.com",
  "age": 30,
  "is_active": true
}

Generated SQL

CREATE TABLE users (
  id INTEGER NOT NULL,
  name VARCHAR(255) NOT NULL,
  email VARCHAR(255) NOT NULL,
  age INTEGER NOT NULL,
  is_active BOOLEAN NOT NULL
);

Type Mapping Rules

The converter applies the following default mappings:

JSON type	SQL type
number (integer)	INTEGER
number (float)	DECIMAL or DOUBLE PRECISION
string	VARCHAR(255)
boolean	BOOLEAN
null	inferred from context or TEXT

Table Naming

By default the converter derives the table name from the root key or uses a generic name like my_table. You can override it in the tool options. Best practice is to use snake_case and plural nouns for table names (e.g., users, order_items).

Column Naming

JSON keys are converted to snake_case if they are in camelCase. For example, firstName becomes first_name. This follows the SQL convention used by PostgreSQL, MySQL, and most ORMs.

A simple flat object is the foundation for all other conversions. Once you understand this basic mapping, you can move on to handling nested objects, arrays, and constraints.