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EXCEPT (Entity SQL)

Returns a collection of any distinct values from the query expression to the left of the EXCEPT operand that are not also returned from the query expression to the right of the EXCEPT operand. All expressions must be of the same type or of a common base or derived type as expression.

expression EXCEPT expression

Arguments

  • expression
    Any valid query expression that returns a collection to compare with the collection returned from another query expression.

Return Value

A collection of the same type or of a common base or derived type as expression.

Remarks

EXCEPT is one of the Entity SQL set operators. All Entity SQL set operators are evaluated from left to right. The following table shows the precedence of the Entity SQL set operators.

Precedence Operators

Highest

INTERSECT

UNION

UNION ALL

EXCEPT

Lowest

EXISTS

OVERLAPS

FLATTEN

SET

Example

The following Entity SQL query uses the EXCEPT operator to return a collection of any distinct values from two query expressions. The query is based on the AdventureWorks Sales Model. To compile and run this query, follow these steps:

  1. Follow the procedure in How to: Execute a Query that Returns StructuralType Results (EntityClient).

  2. Pass the following query as an argument to the ExecuteStructuralTypeQuery method:

(SELECT product from AdventureWorksEntities.Product as product 
    where product.ListPrice  > 20 ) except 
    (select product from AdventureWorksEntities.Product as product 
    where product.ListPrice > 50)

The output is shown below:

ProductID: 707
Name: Sport-100 Helmet, Red
ProductNumber: HL-U509-R
MakeFlag: False
ProductID: 708
Name: Sport-100 Helmet, Black
ProductNumber: HL-U509
MakeFlag: False
ProductID: 711
Name: Sport-100 Helmet, Blue
ProductNumber: HL-U509-B
MakeFlag: False
ProductID: 713
Name: Long-Sleeve Logo Jersey, S
ProductNumber: LJ-0192-S
MakeFlag: False
ProductID: 714
Name: Long-Sleeve Logo Jersey, M
ProductNumber: LJ-0192-M
MakeFlag: False
....

See Also

Concepts

Entity SQL Reference

Other Resources

Set Operators