JSON Schema → PostgreSQL SQL Migrations

About this tool

Compare two database structures in the JSON format shown below and generate PostgreSQL migration SQL. Review the generated statements and test them on a disposable database before use.

How to use it

Paste the old and new database structures as JSON. The tool compares them and generates PostgreSQL ALTER statements. DROP operations can delete data; inspect the script before running it.

Supported operations

CREATE TABLE — create tables
DROP TABLE — remove tables
ADD COLUMN — add columns
DROP COLUMN — remove columns
ALTER COLUMN — change data types
CREATE INDEX — create indexes
DROP INDEX — remove indexes

JSON input format

{
  "tables": {
    "users": {
      "columns": {
        "id": {
          "type": "SERIAL",
          "primary_key": true
        },
        "name": {
          "type": "VARCHAR(255)",
          "nullable": false
        }
      },
      "indexes": ["name"]
    }
  }
}

Original schema (OLD): JSON describing the current database structure

New schema (NEW): JSON describing the target database structure

Comparison result

Tables: --

Columns: --

Indexes: --

Include DROP operations

PostgreSQL migration SQL:

Operations:

PostgreSQL data types

Numeric

SERIAL, BIGSERIAL
INTEGER, BIGINT
DECIMAL(p,s), NUMERIC(p,s)
REAL, DOUBLE PRECISION

Text

VARCHAR(n), CHAR(n)
TEXT
UUID

Date and time

DATE
TIME, TIMESTAMP
TIMESTAMPTZ

Other

BOOLEAN
JSON, JSONB
BYTEA

JSON Schema → DB Diff: PostgreSQL Migrations