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Return the Set Union of Two Sequences

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Use the Union operator to return the set union of two sequences.

Example

This example uses Union to return a sequence of all countries/regions in which there are either Customers or Employees.

var infoQuery =
    (from cust in db.Customers
    select cust.Country)
    .Union
        (from emp in db.Employees
        select emp.Country)
;

Dim infoQuery = _
    (From cust In db.Customers _
     Select cust.Country) _
    .Union _
        (From emp In db.Employees _
         Select emp.Country)

In LINQ to SQL, the Union operator is defined for multisets as the unordered concatenation of the multisets (effectively the result of the UNION ALL clause in SQL).

For more info and examples, see Queryable.Union.

See also