Question: I am getting a bug when I use a text\_area in my rails app. The box takes line breaks, and makes them indentation. Here is a screen shot, any idea where these indentations are coming from?

<https://files.getdropbox.com/u/312568/Picture%2031.png>

Answer: 
Only by iterating over the rows, as [Utaal noted in this answer](https://stackoverflow.com/questions/1080071/get-all-values-of-a-column-from-a-dataset/1080084#1080084).

You might expect that the `DataTable.DefaultView.RowFilter` would support grouping, but it does not (it mainly offers the equivalent functionality of a `Where` clause, with some basic aggregations - though not simple grouping).
In addition to Utaal's answer, you can possibly populate a new DataTable object with the results of a query that selects only one column from your original data source, assuming it's an RDBMS. This has the advantage of letting you specify things that are easy to express in code but easy to express in SQL like `DISTINCT` queries.