为什么我只使用where参数从数据库表中获取单个值？

Question

I have a table named "Registered_User" , which contains two attributes : 1. FavGenre 2. id_User.

One user may have more than one favourite genre. The table data looks like this :

 FavGenre  |  id_User
 1         |  2
 3         |  2
 5         |  2

What I'm basically trying to do, is to get all the favourites genres of user with an ID=2 . So my expected return in this case would be the numbers 1, 3 and 5 .

I'm trying to use this sequence to get that result : var genres = db.Registered_User.Where(x => x.id_User == 2).ToList(); return View(genres); var genres = db.Registered_User.Where(x => x.id_User == 2).ToList(); return View(genres);

But the result I get is :

Genre |  User
1        2
1        2
1        2

Obviously that's not the correct result, it seems like it only takes the first FavGenre value and just repeats it.

So my question would be is the sequence I'm using not right for my purposes? Or does it seem there might be some kind of errors elsewhere (I was thinking that maybe there is something wrong the database or the exact table itself)?

Answer 1

That is because the condition you gave "Where(x => x.id_User == 2)" will return the first results after the condition is met and not look any further. That is since the condition meets the result that "user = 2" is "genre =1", it will only return that. So you have to use a loop to check all the corresponding values to "user=2". I hope this was helpful. :3