Column 'Users.Name' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause

Question

I have the following tables:

create table User 
(
    Id int not null primary key clustered (Id),
    Name nvarchar(255) not null
)

create table dbo.UserSkill 
(
    UserId int not null, 
    SkillId int not null,
    primary key clustered (UserId, SkillId)
)

Given a set of Skills Ids I need to get the users that have all these Skills Ids:

select Users.*
from Users 
inner join UserSkills on Users.Id = UserSkills.UserId 
where UserSkills.SkillId in (149, 305) 
group by Users.Id
having count(*) = 2

I get the following error:

Column 'Users.Name' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.

What am I missing?

Side questions:

• Is there a faster query to accomplish the same result?
• How can I pass the SkillsIds, e.g. (149, 305) as a parameter? And set the @SkillsIds count in having count(*) = 2 instead of 2?

UPDATE

The following code is working and I get the User John.

declare @Users table  
               (
                   Id int not null primary key clustered (Id),
                   [Name] nvarchar(255) not null
               );

declare @Skills table 
                (
                    SkillId int not null primary key clustered (SkillId)
                ); 

declare @UserSkills table 
                    (
                        UserId int not null, 
                        SkillId int not null,
                        primary key clustered (UserId, SkillId)
                    ); 

insert into @Users
values (1, 'John'), (2, 'Mary');

insert into @Skills
values (148), (149), (304), (305);

insert into @UserSkills
values (1, 149), (1, 305), (2, 148), (2, 149);

select u.Id, u.Name
from @Users as u
inner join @UserSkills as us on u.Id = us.UserId
where us.SkillId in (149, 305)
group by u.Id, u.Name
having count(*) = 2

If user has 40 columns, is there a way to not enumerate all the columns in the Select and Group By since Id is the only column needed to group?

Answer 1

First, your tables are broken, unless Name has only a single character. You need a length:

create table User (
  UserId int not null primary key clustered (Id),
  Name nvarchar(255) not null
);

Always use a length when specifying char(), varchar(), and related types in SQL Server.

For your query, SQL Server, is not going to process select * with group by. List each column in both the select and group by:

select u.id, u.name
from Users u join 
     UserSkills us
     on u.Id = us.UserId 
where us.SkillId in (149, 305) 
group by u.Id, u.name
having count(*) = 2;