C# DataTable.Select() - How do I format the filter criteria?

Question

this doesn't work

DataRow[] mySelectedRows = myDataTable.Select("processed <> True");

myDataTable has a row named processed. I would like to select the rows from this table where processed is not equal to True. Can anyone help?

Answer 1

Is processed a bool or a string?

If a bool then "not processed" should work otherwise if its a string "processed <> 'True'" - using single quotes as the delimiters within the where string. It would be worth checking the values in the table/column at the point at which you're querying the data to make sure you're testing against the right thing (this has bitten me in the past).

Answer 2

This should work just fine, but it will not return rows where processed is null .

To include nulls, try this:

DataRow[] rows = myDataTable.Select("isnull(processed, false) <> true"); 

SQL null is an indeterminate value. It does not equal the boolean value true , but it does not not equal true either. (See Null (SQL) .)

For the general filter expression reference, see the DataColumn.Expression MSDN topic .