LINQ to SQL and Entity Framework both are designed for ORM (Object Relational Model) support. They are developed to avoid the difficulties involved in writing Object Oriented code to perform RDMS operations. The OOP and RDMS are conceptually very different. The question arises when to use LINQ2SQL and when to use Entity Framework. What is the different between LINQ to SQL and Entity Framework.

LINQ to SQL and the Entity Framework have a lot in common, but each has features targeting different scenarios. While speaking about similarities or differences, I understand that ADO.NET Entity Framework’s LINQ to Entities can be considered as superset of LINQ to SQL and that, ADO.NET Entity Framework is much more than LINQ to Entities.

LINQ to SQL always considered as a rapid development tool for applications that query Microsoft SQL Server databases using objects that map directly to SQL Server schemas.  LINQ to Entities supports more flexible mapping of objects to Microsoft SQL Server and other relational databases through extended ADO.NET Data Providers.

When an application requires any of the following features, we should use the ADO.NET Entity Framework:

• The ability to define more flexible mapping to existing relational schema, for example:
  • Mapping a single class to multiple tables
  • Mapping to different types of inheritance
  • Directly Modeling Many to Many relationships
  • Mapping to an arbitrary query against the store
• The ability to query relational stores other than the Microsoft SQL Server.
• A full textual query language.
• The ability to query a conceptual model without materializing results as objects

 

If application does not require any of these features, LINQ to SQL would be the better choice because it provides rapid development. LINQ to SQL is targeted at rapid-development scenarios against Microsoft SQL Server and provides a simpler approach and richer design experience for applications with data classes that map directly to the schema of your Microsoft SQL Server database.