| Feature |
Entity Framework Implementation |
LINQ to SQL Implementation |
| Supported databases |
Any relational database with an Entity Framework-enabled ADO.NET data provider; SQL Server 200x is the default; Third-party providers for IBM-DB2,
Firebird, Informix, Ingres, MySQL, Oracle, PostgreSQL, SQLite and VistaDb are available or in development |
SQL Server 200x and partial (non-
graphical) support for SQL Server
Compact Edition 3.5 only |
| Inheritance model |
Table per type, table per concrete type, table per
hierarchy |
Table per hierarchy only |
| Type and collection names |
Independent; it’s typical to edit type names to
singular and accept default plural collection names |
Type and collection names are the same; names are singularized by default |
| Schema independence |
Three-tier mapping layer makes domain object model independent to database schema; can map multiple tables to a single entity or vice versa |
Direct, one-to-one mapping; Domain objects are created directly from the database and bound to its schema |
Update model when
database schema changes |
Automated |
Manual |
| Graphical designer |
Multi-pane entity view with tree-view Model Browser and tabular table column to property mapping window |
Dual-pane class view with Methods pane for stored procedure assignment |
Three-tier WCF
service architecture |
"Perseus" add-on code enables serializing CRUD
operations between physical tiers with WC |
LINQ to SQL has no "out-of-the box
n-tier story" |
| Many:many relations |
Supported without relation table if no payload |
Relation table required |
| Complex (value) types |
Supported |
Not supported |
| Loading related entities |
Explicit load instruction required; eager loading is
the default |
Implicit lazy loading is the default; explicit eager loading is optional |
Related entity loading management for sort
order and depth |
Requires use of the EntityCollection.Attach() and
EntitySet.CreateSourceQuery() methods |
Simple LINQ predicates or stored procedures applied to DataContext |
Foreign key value
visibility |
Not visible; association endpoints (EntityReferences and EntitySets) replace foreign keys |
Visible; foreign keys supplement association endpoint |
| High-performance, low-overhead DataReaders |
Supports hierarchical/polymorphic DataReaders |
Not supported |
| Query languages |
LINQ to Entities, Entity SQL, and ObjectQuery (uses
Entity SQL) |
LINQ to SQL (most Standard Query
Operators) |
| Stored procedure support |
All CRUD operation |
All CRUD operation |