DEVONthink Pro features its own document type for tabular data named ‘sheet’. Sheets resemble spreadsheets and can hold textual data organized in rows and columns. Create a new sheet with Data > New > Sheet, name it, and add some columns with Data > Sheet > New Column or Edit Columns.
To add new rows, use Data > Sheet > New Record; alternatively you can use the contextual menu for all these operations, too. Rearrange columns by dragging their headers with the mouse, sort by a column by clicking its header. Of course, sheets are fully searchable; sheets store plain text and so they do not support rich text, images, or links to other documents yet.