Question

I have a question regarding LINQ to SQL. I would like to write the following query in LINQ:

SELECT DISTINCT([Column]),
       COUNT([Column]) as [Count]
FROM [Table]

Can I do this in 1 query? Or do I have to initially select my distinct columns, and then for each select the count? That seems very clumsy and heavy (n-squared).

Answer 1

That query isn’t legal, as you’re using an aggregate (COUNT) without grouping on the column that you’re selecting.

What you want is something like this:

select [Column], Count([Column]) as [Count] from [Table] group by [Column]

That’s easily expressed in LINQ to SQL.

from x in context.Table 
group x by x.Column into grp
select new { Column = grp.Key, Count = grp.Count() }