I'm not sure if an answer for this already exists, as I can't figure out what mechanism in Linq is meant for this situation, or if I just need to do it manually.
Let's say I have 2 tables:
------------Employees-------------
EmployeeID Name -other columns-
---------EmployeeSkills-----------
EmployeeID Skill -other columns-
So each employee can have 0 or more skills.
My goal is to draw this information into a data structure in memory, using one sql query
class StaticEmployee
{
int EmployeeID;
string Name;
List<string> Skills;
}
List<StaticEmployee> employees = (???).ToList();
Since my table relations are setup, I could just foreach the employees table (from employee in db.Employees select employee), however when I access the EmployeeSkills property, it is going to execute a seperate query for every employee record since that data wasn't returned with the first query.
Alternatively, and I what I want done so far as Sql is concerned, is run a query with a left join:
SELECT Employees.EmployeeID, Employees.Name, EmployeeSkills.Skill FROM Employees LEFT JOIN EmployeeSkills ON Employees.EmployeeID=EmployeeSkills.EmployeeID
That will get me my list, but I'll need to manually collate it into my list since an employee with 2 skills will return 2 rows. Is there a Linq operation that does this? Hypothetical example below
from employee in db.Employees
select new
{
EmployeeID = employee.EmployeeID,
Name = employee.Name,
Skills = new List(
from employeeSkill in employee.EmployeeSkills
select employeeSkill.skill
)
}