# Return the Set Union of Two Sequences

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).