.EDMX File Extension

A .EDMX file is a ADO.NET Entity Data Model Designer File, created by Microsoft.

Open with Microsoft Visual Studio 2022+. Available for Windows.

What is a .EDMX file?

The .EDMX file extension stands for ADO.NET Entity Data Model Designer File. This type of file is used with Microsoft Visual Studio, a program for creating applications. The .EDMX file contains a data model which is a structured representation of a database's schema. This schema includes details about the database tables (referred to as entities), the columns in these tables (called fields), and the relationships between these tables, such as one-to-one or one-to-many relationships.

To open and work with an .EDMX file, you need to use Microsoft Visual Studio 2022 or a newer version. This file is particularly important for developers working with SQL Server databases because it helps in generating the database schema automatically.

Inside an .EDMX file, there are three important types of metadata files: 1. Conceptual Schema Definition Language (CSDL) file: This file describes the structure of the data as seen by the application. 2. Store Schema Definition Language (SSDL) file: This file describes the structure of the data as stored in the database. 3. Mapping Specification Language (MSL) file: This file maps the conceptual schema to the storage schema, detailing how data moves from the application to the database.

To create an .EDMX file, you must use a version of Microsoft Visual Studio that includes the ADO.NET Entity Data Model Designer tool. This tool provides a visual interface for designing the data model and automatically generates the necessary metadata files.


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