VS 2008 SP1 +. NET 3.5 SP1 (2)

Entity Framework (Entity Framework) One of the Linq to Entities

Introduced

Using Northwind as the sample database, the LINQ to Entities of the Ado.net Entity framework

First-Returns the number one member in the collection;

FirstOrDefault-Returns the first member in the collection (returns null if it is not found);

All-whether all members in the collection meet a condition; no delay

Any-whether any of the members in the collection meet a condition; no delay

Average-take average; no delay

Sum-sum; no delay

Max-maximum value; no delay

Min-Take minimum value; no delay

Count-takes the number of members of the specified collection, returns the value type int;

LongCount-takes the number of members of the specified collection, returns a value type long;

Take-Gets the first n members of the collection;

Skip-Skips the first n members of the collection; delay (Linq to entities needs to be sorted before skip)

DISTINCT-Filters the same items in the collection;

Union-Joins different sets, automatically filters the same item;

UnionAll-Joins different sets, does not automatically filter the same item;

Concat-Joins different sets, does not automatically filter the same item;

Intersect-Gets the same item (intersection) of different sets;

Except-Deletes the same item from a collection as it does in another collection;