Evandro's mailing lists (Please, don't send personal messages to this address) wrote:
I'm doing a PhD in data mining and I need more than 1600 columns. I got an
error message saying that I can not use more than 1600 columns.
 It is happening because I have to change categorical values to binary
creating new columns.

Perhaps you don't want a relational database at all if you are stretching it to match your client application in this way. Do I have it right that you have something like

Table: bird_sighting_facts (bird, category, value)
  1 | wingspan    | 120mm
  2 | beak-colour | red
  3 | chest-colour| blue
...

And are converting it into:
expanded_bird_facts (bird, cat_wingspan, cat_beak_colour, cat_chest_colour, ...)

In which case since you'll almost certainly be throwing away any relational integrity you had in the first case I'd just throw a lightweight wrapper around some dbfile files or similar.

--
  Richard Huxton
  Archonet Ltd

---------------------------(end of broadcast)---------------------------
TIP 4: Have you searched our list archives?

              http://archives.postgresql.org
  • ... Richard Huxton
    • ... Tom Lane
    • ... Tino Wildenhain
    • ... Randal L. Schwartz
      • ... Evandro's mailing lists (Please, don't send personal messages to this address)
        • ... Richard Huxton
        • ... John D. Burger
          • ... Jim C. Nasby
          • ... Evandro's mailing lists (Please, don't send personal messages to this address)
            • ... Tino Wildenhain
            • ... Chris Travers

Reply via email to