When creating ER diagrams with draw.io
Use sliding connectors: When drawing connectors for relationships, make sure you hover over the shape until the outline turns blue – don’t connect it to one of the connection points. This way, when you drag the shapes around to make room, the connectors will ‘slide’ or ‘float’ into the right positions.
Use template shapes: Use the scratchpad for storing groups of shapes so you don’t have to build each up from scratch. If you are creating the second style of ER diagram, you can store a ‘template’ with as many extra ‘rows’ for the attributes as you typically need. See this earlier post for a more detailed description on how to use the scratchpad in draw.io to make creating ER diagrams quick and easy.
Export to text: Want to create a text list of entities and their attributes and keys? Use the draw.io text plugin and export it to a text file. This works better with the second style of diagram.
Add extra attributes to entities: Sometimes your entity shapes don’t have enough space for all the attributes you need. The easiest way is to duplicate an existing attribute row. Select an existing row and press CTRL+Enter (or CMD+Enter on MacOS) to duplicate it. You can also right click on the row shape, select duplicate, then edit the text. Of course, you can also drag new attribute rows from the shape library and drop them within the entity shape.
Edit an attribute row by selecting it, then pressing Enter. When you’ve finished, press CTRL+Enter (CMD+Enter) to exit the text edit. Use the arrow keys to move to the next entity or duplicate it by pressing CTRL+Enter (or CMD+Enter on MacOS).