How to select a single column with Entity Framework

Question

Is there a way to get the entire contents of a single column using Entity Framework 4  The same like this SQL Query   SELECT Name FROM MyTable WHERE UserId   1

User · Answer

I m a complete noob on Entity but this is how I would do it in theory     var name   yourDbContext MyTable Find 1  Name    If It s A Primary Key   -- OR --  var name   yourDbContext MyTable SingleOrDefault mytable   gt  mytable UserId    1  Name    -- OR --  For whole Column   var names   yourDbContext MyTable  Where mytable   gt  mytable UserId    1   Select column   gt  column Name     You can   ToList     this       But  oh Geez Rick  What do I know

User · Answer

Using LINQ your query should look something like this   public User GetUser int userID    return    from p in  MyTable     Your Entity Model   where p UserID    userID  select p Name   SingleOrDefault         Of course to do this you need to have an ADO Net Entity Model in your solution

User · Answer

If you re fetching a single item only then  you need use select before your FirstOrDefault   SingleOrDefault    And you can use anonymous object of the required properties   var name   dbContext MyTable Select x   gt  new   x UserId  x Name    FirstOrDefault x   gt  x UserId    1   Name    Above query will be converted to this   Select Top  1  UserId  Name from MyTable where UserId   1    For multiple items you can simply chain Select after Where   var names   dbContext MyTable Where x   gt  x UserId  gt  10  Select x   gt  x Name     Use anonymous object inside Select if you need more than one properties

User · Answer

You can use LINQ s  Select   to do that  In your case it would go something like   string Name   yourDbContext    MyTable    Where u   gt  u UserId    1     Select u   gt  u Name     SingleOrDefault       This is what actually executes the request and return a response   If you are expecting more than one entry in response  you can use  ToList   instead  to execute the request  Something like this  to get the Name of everyone with age 30   string   Names   yourDbContext    MyTable    Where u   gt  u Age    30     Select u   gt  u Name     ToList

User · Answer

You could use the LINQ select clause and reference the property that relates to your Name column

[c#] How to select a single column with Entity Framework?

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