How to compare 2 columns if they are equal and output it on a new column using LINQ

I want to compare 2 column under the same data table. If the 2 columns have the same value then the answer will be “Success” however if it’s not the answer will be “Failed” on a new column. we already tried for each, it works but it takes too long because our files contains 60k-140k rows. I hope someone can help me. Thanks

give a try on following

Clone your datatable (ensure the Result column holding failed, success is not present) - dtResult
Add a datacolumn (should be on end of columns) ColName Result

Assign activity
Left: dtResult

(From d in dtData.AsEnumerable
let chl = d(Col1).toString.Trim.Equals(d(Col2).toString.Trim)
Let res = If(chk, “Success”, “Failed”)
Let ra = d.ItemArray.Append(res).toArray
Select r=dtResult.Rows.add(ra)).CopyToDataTable