LINQ group by 3 columns but display all of them

[drago47]

Hello!

I have a table…

And I want to group by Col2 and Col9
And the output should be

(From d In dt.AsEnumerable
Group d By k1=d("Col1").toString.Trim, k2=d("Col2").toString.Trim Into grp=Group
Let ra = New Object(){k1,k2, ? ? ? ? ? }
Select test.Rows.Add(ra)).CopyToDataTable

I ve tried the code above only with k1 and k2… but i need all columns

[ppr (Peter)]

its depending on how you have decide from which group member to take the value
in case of taking it from first group member we would use for ?
grp.First()(YourColNameOrIndex)

[drago47]

@ppr yeah! first would be nice so… let me give a shot.

[ppr (Peter)]

but keep in mind your output

@drago47

And the output should be

looks more as it is taking the distinct rows, where the distinct value evaluation is done over all row columns

[drago47]

yes, you are totally right. to avoid losing distinct data - those columns need to be included in the group by. Correct?

[ppr (Peter)]

we can do:

• using remove duplicate row activity
• YourDataTableVar.DefaultView.ToTable(True, {ColNameFirst,ColNameLast})
• LINQ

Also have a look here:

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