Question

Given the code below. What statement is correct?

"var query = from employee in employees
join student in students
on new {employee.FirstName, employee.LastName } equals new {student.FirstName, student.LastName } select employee.FirstName + " " + employee.LastName;"
a. The query uses one data source and one property for join.
b. The query uses one data source and two properties for join.
c. The query uses two data sources and one property for join.
d. The query uses two data sources and two properties for join.

Answer 1

In the given query, two data sources are being utilized, and a join operation is performed based on two properties from these sources. This implies that the query involves combining or linking information from two distinct datasets by matching values in specified properties to create a comprehensive result set.

The correct statement is d. The query uses two data sources and two properties for join.

Step-by-step explanation:

In the code given, the query uses the join keyword to combine two data sources, employees and students. It then specifies the properties to be compared for the join using the new {employee.FirstName, employee.LastName } and new {student.FirstName, student.LastName } statements. The result of the join is a collection of objects with the employee's full name.

Therefore, the query uses two data sources (employees and students) and two properties (employee.FirstName and employee.LastName) for the join.