How To Build an ER Diagram with Mermaid Chart
• 4 mins
An entity relationship (ER) diagram acts like a blueprint for your database. This makes ER diagrams effective tools for anyone dealing with complex databases, data modeling, and AI model training.
It doesn’t matter if you’re a seasoned data professional or just dipping your toes in the data pool: mastering ER diagrams is a helpful skill. Traditionally, crafting an ER diagram online meant grappling with clunky drawing tools with graphical user interfaces.
Mermaid Chart is an AI native diagramming software that offers the best way to create your ER diagram online. Our Mermaid AI functionality allows you to build an ER diagram in seconds and edit the draft to completion in our whiteboard or Mermaid JS editor.
It’s fast, simple, and powerful. If you’re new to Mermaid Chart, you can create an account to get started for free.
Let’s dive deeper into ER diagrams and show you how to get started with Mermaid Chart:
What is an ER Diagram?
An ER diagram is a graphical representation that helps illustrate the structure, components, and flow of a database. A well-designed ER diagram will help communicate how the entities connect and relate to each other and how data flows between those entities.
This diagram type is typically used in the conceptual design portion of system development, as it allows for clear visualization of the relationships between the entities within the database. They can be helpful in creating the database design and ensuring the requirements are covered. ER diagrams are also often used as a means of documenting an existing database.
Quality databases provide the fuel that AI models and algorithms run on. ER diagrams help inspire more structured and comprehensive database design, making them an important tool in supporting the widespread use of AI.
How to quickly build an ER diagram online with Mermaid AI
Since ER diagrams are helpful for building AI models, it’s only right that we use Mermaid AI to help you create your visuals!
Quick note: Pro and Enterprise users have unlimited access to Mermaid AI. You can find info on our plans here. Mermaid AI is currently limited for users on the Free tier.
Start by creating an account and clicking the new diagram button on your dashboard. You’ll have the option to start the diagram with Mermaid AI in the top middle of your screen. (see below)
Toggle to the “Mermaid AI” tab from the Editor tab at the center of the screen if not automatically selected. The sample prompts provided on the Mermaid AI chat screen will correspond to the diagram type you’ve selected. In this case, you’ll see various sample prompts: “Create an ER diagram from a database schema”, “Create an ER diagram for database design,” etc.
If you’re looking for a basic starting point, select one of the sample prompts to get started.
Mermaid AI will quickly generate a starting point for your ER diagram. You can view the diagram in full screen, or pan and zoom to check out different entities or relationships.
Message Mermaid AI again with the more specific details of your system: what the database includes, the use case, what kind of data you’re inputting, where the data comes from, etc. This will help Mermaid AI fine-tune your visual and get closer to a final draft.
For example, you might say “Tweak this diagram to showcase how entities interact within a social media platform,” to achieve the following visual:
At any point, you can click the Edit button or toggle back to the Editor tab to manually edit your diagram using the editor.
Once your diagram is ready to go, click the Export button on the left side menu to save it as a PNG or SVG file. If you’re chatting with Mermaid AI, the Export button will be located at the top of your generated diagram, next to the Full Screen button. You can also share the diagram using the share button on the top right of your screen.
You may also hit the hamburger icon (the three dots) and save your Mermaid AI output as a new diagram.
How to get started with Mermaid Chart as an ER diagram online tool – for free!
Get started by creating your free Mermaid Chart account here. If you have any questions about ER Diagrams, Mermaid, or Mermaid Chart please reach out to us at hello@mermaidchart.com. We’re happy to help.