An entity in this context is an object, a component of data. Software to draw er diagram from database. From there, drag each of your tables onto the canvas, and Lucidchart will automatically draw lines between entities, based on the relationships in your database structure. Cloud- based Database & ERD Software The easiest online database and ER diagram & collaboration tool for your team Start Free Trial. Entity Relationship ( ER) Diagram: Example showing relationship of student enrollment. An entity relationship diagram ( ERD) shows the relationships of entity sets stored in a database. Allows saving your diagrams to cloud storage services like GDrive, Dropbox and OneDrive, or to your own computer Entity Relationship Model: Example showing relationship of student enrollment. Allows different types of charts like flowcharts, org charts, UML, ER and network diagrams. Entities are the things we need to store data about.Io is a free online diagram software for making flowcharts, process diagrams, etc. Entity Relationship Diagram, also known as ERD, ER Diagram or ER model, is a type of structural diagram for use in database design. The entity relationship model has the purpose of make a model of the problem and let you understand the problem, so in the end you can generate a good relational model.