SQL → DBML Converter | ERD Generator Docs

The SQL → DBML Converter lets you import existing SQL schema scripts and instantly transform them into DBML (Database Markup Language).
This enables fast ERD generation, visual exploration, and further customization — without manually rewriting schemas.

Whether you’re migrating a legacy database or reviewing a production schema, this tool provides a clean, readable DBML output ready for diagrams.

🚀 Why Convert SQL to DBML?

SQL schemas are powerful but often:

• Dialect-specific
• Verbose
• Hard to visualize

DBML offers a database-agnostic, human-readable format that works seamlessly with ERD Generator.

Key benefits:

• Instant ERD visualization
• Cleaner schema documentation
• Easier collaboration across teams
• One source of truth for diagrams and exports

🧭 Supported Source Types

The converter supports multiple input formats and SQL dialects:

type SourceType =
  | "dbml"
  | "mysql"
  | "postgres"
  | "json"
  | "mssql"
  | "postgresLegacy"
  | "mssqlLegacy";

Supported SQL Dialects

🛠️ How the SQL → DBML Conversion Works

Step 1: Paste or Import SQL

• Paste your CREATE TABLE, ALTER TABLE, and constraint definitions
• Or import schema files directly

Step 2: Select Source Type

Choose the correct SQL dialect to ensure accurate parsing and constraints mapping.

Step 3: Automatic Conversion

The engine:

• Extracts tables and columns
• Maps primary & foreign keys
• Converts indexes and constraints
• Normalizes output into valid DBML

Step 4: Live Diagram Preview

The generated DBML renders instantly in the diagram canvas for validation and refinement.

🧱 Example Conversion

Input (PostgreSQL)

CREATE TABLE users (
  id SERIAL PRIMARY KEY,
  email VARCHAR(255) UNIQUE NOT NULL,
  created_at TIMESTAMP DEFAULT now()
);

Output (DBML)

Table users {
  id int [pk, increment]
  email varchar(255) [unique, not null]
  created_at timestamp [default: now()]
}

The output is clean, readable, and ready for ERD visualization.

⚠️ Best Practices for Accurate Conversion

1. Use Complete Schemas

• Include all CREATE TABLE statements
• Ensure foreign keys are defined explicitly

2. Avoid Mixed Dialects

• Don’t mix MySQL and PostgreSQL syntax in the same input
• Select the correct SourceType before conversion

3. Prefer Explicit Constraints

• Named constraints improve relationship detection
• Inline foreign keys convert more reliably

🧩 Common Conversion Limitations

Some SQL features may not map 1 to DBML:

• Database-specific functions
• Triggers and stored procedures
• Advanced index types
• Vendor-specific column attributes

These are safely ignored or converted into notes when possible.

🛠️ Troubleshooting Conversion Errors

❌ Syntax Error

Cause: Unsupported or malformed SQL
Fix: Validate SQL or switch to legacy source type

❌ Missing Relationships

Cause: Foreign keys defined outside table scope
Fix: Ensure FK constraints are present in schema input

❌ Duplicate References

Cause: Multiple identical foreign keys
Fix: Remove duplicate ALTER TABLE references before conversion

🔄 After Conversion: What You Can Do Next

Once converted to DBML, you can:

• Edit schemas in the DBML editor
• Apply layouts (Left → Right, Force-Directed)
• Customize table themes and backgrounds
• Filter visible tables via sidebar
• Drag and arrange tables freely
• Export diagrams as PNG / JPG
• Convert DBML back to SQL using DBML → SQL

⌨️ Productivity Tips

• Ctrl / Cmd + S — Save schema
• Ctrl / Cmd + B — Format DBML
• Ctrl / Cmd + Q — Command palette
• Use multiple tabs for side-by-side schemas
• Organize work using folders & workspaces

📌 Summary

The SQL → DBML Converter bridges the gap between existing databases and modern visual modeling.
It allows you to move faster, document better, and reason about your schema visually — without rewriting everything from scratch.

Use it as the starting point for every ERD.