Linq to Entities 대신 Linq-to-SQL을 사용하는 LinqPad를 사용했지만 개념은 동일해야합니다.
먼저 테스트 할 때 사용한 데이터.
create table People (PersonID int, Name varchar(100))
create table Skills (SkillID int, Skill varchar(100))
create table PeopleSkills (PeopleSkillsID int, PersonID int, SkillID int)
insert People values (1,'Bert'),(2,'Bob'),(3,'Phil'),(4,'Janet')
insert Skills values (1,'C#'),(2,'Linq'),(3,'SQL')
insert PeopleSkills values (1,1,1),(2,1,2),(3,1,3),(4,2,1),(5,2,3),(6,3,2),(7,3,3),(8,4,1),(9,4,2),(10,4,3)
그리고 해결책.
//I don't know how you are specifying your list of skills; for explanatory purposes
//I just generate a list. So, our test skill set is C#, Linq, and SQL.
//int? is used because of LinqToSQL complains about converting int? to int
var skills = new List<int?>(){1,2,3};
//This initial query is also a small bow to LinqToSQL; Really I just wanted a plain
//List so that the Except and Any clauses can be used in the final query.
//LinqToSQL can apparently only use Contains; that may or may not be an issue with
//LinqToEntities. Also, its not a bad idea to filter the people we need to look at
//in case there are a large number anyway.
var peopleOfInterest = PeopleSkills.Where(p => skills.Contains(p.SkillID)).ToList();
//Final query is relatively simple, using the !x.Except(y).Any() method to
//determine if one list is a subset of another or not.
var peopleWithAllSkills =
//Get a distinct list of people
from person in peopleOfInterest.Select(p=>p.PersonID).Distinct()
//determine what skills they have
let personSkills = peopleOfInterest.Where(x=>x.PersonID == person).Select(x=>x.SkillID)
//check to see if any of the skills we are looking for are not skills they have
where !skills.Except(personSkills).Any()
select person;
나는 이것을 약간의 생각을하고 싶다; 다른 누군가가 이미 그렇게하지 않았다면 나는 포괄적 인 대답으로 다음 24 시간 이내에 다시 연락 할 것입니다. –