using (SchoolEntities context =
    new SchoolEntities())
{
    // The following three queries demonstrate 
    // three different ways of passing a parameter.
    // The queries return a string result type.

    // Use the parameter substitution pattern.
    foreach (string name in context.ExecuteStoreQuery<string>
        ("Select Name from Department where DepartmentID < {0}", 5))
    {
        Console.WriteLine(name);
    }

    // Use parameter syntax with object values.
    foreach (string name in context.ExecuteStoreQuery<string>
        ("Select Name from Department where DepartmentID < @p0", 5))
    {
        Console.WriteLine(name);
    }
    // Use an explicit SqlParameter.
    foreach (string name in context.ExecuteStoreQuery<string>
        ("Select Name from Department where DepartmentID < @p0",
            new SqlParameter { ParameterName = "p0", Value = 5 }))
    {
        Console.WriteLine(name);
    }
}

------解决方案--------------------
要不你就把SQL查询封装在存储过程里，再通过EF访问这个存储过程。