From SQL to Diagram: Your First Schema

ERD Factory turns a CREATE TABLE dump into a diagram — no schema designer to learn first, if you already have SQL. This article covers that path. If you don’t have any SQL yet, see Starting From Scratch: Designing a Schema with Schema Builder instead — both land you in the same diagram either way.

1. Open a new schema

From a project, opening a new schema drops you straight into DDL mode — the first tab in the mode switcher — rather than an empty canvas. You’ll see a dialect picker, a large text area, and a “try a sample schema” link if you want to see the flow before pasting your own SQL. If the text area is still empty, a callout above it also offers a Use Schema Builder button — see the from-scratch article above if you’d rather describe what you want than write the SQL yourself.

2. Paste your DDL

Paste one or more CREATE TABLE statements (and, optionally, standalone CREATE INDEX statements — they get attached to the table they index automatically). See Supported SQL Dialects and DDL Syntax for exactly what the parser understands.

3. Analyze

Click Save & Update to parse the DDL and run relationship inference and gap detection against it. On success, the view switches to Diagram mode automatically so you see the result immediately — you don’t have to click over yourself.

4. Review, then persist

At this point your schema exists only in the current browser session. Nothing above the top-bar Save button writes to your account — analyzing, adding tables, and loading a sample are all local until you explicitly save. Once you’re happy with the diagram, click Save to persist the DDL, schema name, dialect, and any table notes to your project.

From here, explore the diagram, switch to Discovery mode for a denser column-level view, run AI Schema Analysis for suggestions beyond structural gap detection, or describe a feature you want to add via Schema Builder.