c# all distincts value from datatable

Question

I've found this piece of code that can be used to get all distinct values. But my datatable has 10 columns. The distinctValues only shows the columns I write in the toTable(); Is it possible to use this function, but also show the rest of the columns?

DataView view = new DataView(table);
DataTable distinctValues = view.ToTable(true, "Column1", "Column2");

When you say show the rest of the columns and they were different how would they then be distinct? — Belogix, Dec 12 '12 at 12:56
Which row do you want to see when there are multiple rows with the same fields, just the first, all or a special one? — Tim Schmelter, Dec 12 '12 at 12:57
See this thread http://stackoverflow.com/questions/1199176/how-to-select-distinct-values-from-datatable — Sigar Dave, Dec 12 '12 at 13:02

score 1 · Answer 1 · answered Dec 12 '12 at 12:58

Unless those columns you mention are the full key to the table, there is no guarantee that for a particular combination of those two columns the other columns will have exactly one value.

And if they were the key, then there would be no need to use a "distinct" filter.

score 0 · Answer 2 · answered Dec 12 '12 at 13:05

You can use Linq-To-DataTable

var distinct = from row in table.AsEnumerable()
               group row by new
               {
                   Col1 = row.Field<string>("Column1"),
                   Col2 = row.Field<string>("Column2")
               } into Group
               select Group.First()
DataTable tblDistinct = distinctRows.CopyToDataTable();

(assuming that you just want an arbitrary row[the first])

c# all distincts value from datatable

2 Answers2