AI PostgreSQL Schema Generator

VibeSchema is a free AI PostgreSQL generator. Describe your database in plain English and get a complete, runnable PostgreSQL schema with tables, relationships, constraints, and indexes.

The AI works directly in PostgreSQL. This means that you can check the PostgreSQL as you build. Also, this ensures you don’t run into lossy conversion when updating an existing schema, which often happens with tools that use an intermediate format, such as DBML.

The process is simple:

1. Open PostgreSQL mode. Go to PostgreSQL mode in VibeSchema (the button above sends you there directly). Paste an existing schema to start from in Code View, or describe your app in plain English in the chat to get a starting schema.

2. Iterate in chat. Ask the AI to add tables, change column types, introduce constraints, or restructure relationships. The PostgreSQL code updates live as you go, as does the ER diagram.

3. Export when ready. Hit the export button to download your .sql file. Run it directly against your PostgreSQL database using psql, a GUI tool like pgAdmin, or drop it into your migration pipeline.

Example

Here is a real example. The prompt:

Create a basic SaaS app with organizations, users, and projects. Users belong to organizations, projects belong to organizations.

VibeSchema generates the schema instantly:

CREATE TABLE organizations (
  id SERIAL PRIMARY KEY,
  name VARCHAR NOT NULL,
  created_at TIMESTAMP DEFAULT NOW()
);

CREATE TABLE users (
  id SERIAL PRIMARY KEY,
  organization_id INTEGER NOT NULL REFERENCES organizations(id),
  name VARCHAR NOT NULL,
  email VARCHAR NOT NULL UNIQUE,
  created_at TIMESTAMP DEFAULT NOW()
);

CREATE TABLE projects (
  id SERIAL PRIMARY KEY,
  organization_id INTEGER NOT NULL REFERENCES organizations(id),
  name VARCHAR NOT NULL,
  description TEXT,
  created_at TIMESTAMP DEFAULT NOW()
);

From there you keep iterating in chat: add columns, tighten constraints, introduce new tables, rename things. The ER diagram and the code view reflect every change in real time.

No intermediate format

Most AI schema tools generate a neutral intermediate format - DBML, JSON, a graph - and then convert it to PostgreSQL on export. That conversion step is where things go wrong: constraints get dropped, defaults disappear, indexes vanish, types get flattened.

VibeSchema’s PostgreSQL mode works differently. The AI reads and writes PostgreSQL directly. There is no conversion step. The schema in the code view is the schema. When you ask the AI to add a CHECK constraint or a partial index, it writes that into the PostgreSQL source and it stays there.

What is PostgreSQL DDL?

DDL stands for Data Definition Language: the subset of SQL used to define the structure of your database. Unlike DML (Data Manipulation Language), which handles inserting, updating, and deleting records, DDL defines the shape of your data: what tables exist, what columns they have, and how they relate to each other.

Each CREATE TABLE statement tells PostgreSQL exactly what to build: column names, data types, constraints like NOT NULL and UNIQUE, primary keys, and foreign key relationships. This is what VibeSchema generates.

DDL is also safe to re-run when written carefully. Using CREATE TABLE IF NOT EXISTS or pairing your schema with a migration tool like Flyway, Liquibase, or Prisma means you can apply it repeatedly without errors, which matters for team workflows and CI/CD pipelines.

Frequently asked questions

Is it free? Yes. VibeSchema is fully free to use, including PostgreSQL mode and the export.

Do I need to sign up? No. You can generate and export schemas without creating an account.

Can I import an existing PostgreSQL schema? Yes. Paste your existing schema in Code View and VibeSchema will load it as the starting point. You can then iterate from there and re-export when done.

What PostgreSQL version is the output compatible with? The generated SQL is compatible with all modern PostgreSQL versions.

Can I edit the SQL directly? Yes. The code view is editable. You can make changes directly in the SQL, or go back to chat for larger restructuring. Both stay in sync.