Duplicate String Search Query

Question

I read data from an XML file in a DataSet using C #, than I want to identify duplicate (completely identical) rows in this set. I tried this grouping and it works!

var d= from r1 in table.AsEnumerable() group r1 by new { t0 = r1[0], t1 = r1[1], t2 = r1[2], t3 = r1[3], t4 = r1[4], t5 = r1[5], t6 = r1[6], t7 = r1[7], t8 = r1[8], } into grp where grp.Count() > 1 select grp; 

But the number of data columns can be different, so I can not apply static grouping in the query, as indicated above. Should I have generated a grouping array dynamically?

I do not want to delete duplicates, I just want to find them!

Answer 1

 var rows = table.AsEnumerable(); var unique = rows.Distinct(DataRowComparer.Default); var duplicates = rows.Except(unique); // , DataRowComparer.Default); 

Answer 2

try it

 DataTable dt = TableName; dt = oPerformance.RemoveDuplicateRows(dt, ColToCompareAndRemove); 

and here is the function RemoveDuplicateRows

 public DataTable RemoveDuplicateRows(DataTable dTable, string colName) { Hashtable hTable = new Hashtable(); ArrayList duplicateList = new ArrayList(); //Add list of all the unique item value to hashtable, which stores combination of key, value pair. //And add duplicate item value in arraylist. foreach (DataRow drow in dTable.Rows) { if (hTable.Contains(drow[colName])) duplicateList.Add(drow); else hTable.Add(drow[colName], string.Empty); } //Removing a list of duplicate items from datatable. foreach (DataRow dRow in duplicateList) dTable.Rows.Remove(dRow); //Datatable which contains unique records will be return as output. return dTable; }