What is a DBML file?
A .DBML file is primarily a Database Markup Language file. Developers use it to write and visualize database schemas. Holistics created this open-source language, and tools like dbdiagram.io use it to generate Entity-Relationship diagrams.
However, a .DBML file can also be a Visual Studio OR Design File used by Microsoft LINQ to SQL. In this case, the file contains XML code that maps SQL database objects to software classes within Visual Studio.
How to open DBML files?
Because a .DBML file might contain a custom Domain-Specific Language (DSL) for database schemas or standard XML for Microsoft tools, it can be confusing to open. You can view the raw text in basic text editors like Notepad, or advanced editors like Visual Studio Code.
To visualize the schema, use dbdiagram.io or DBeaver for standard Database Markup Language files. If it is a LINQ to SQL file, Visual Studio is the correct software.
Best practices and troubleshooting
If you do not know which format you have, viewer.online/dbml can analyze .DBML files to identify the exact format and creator software, inspect the file structure, extract readable text, and check whether an online preview is available.
Software and tools
Summary
viewer.online/dbml is useful for identifying, inspecting, and understanding .DBML files without installing software or dealing with compatibility problems. It removes the guesswork when you receive an unknown database schema or design file.