[support] CCK - Content types with lots of fields

[jp.stacey at torchbox.com]

> Good to know - this is the kind of info I'm looking to gather.  Anyone else
> know of any caveats?

If you've got 30-50 homogeneous fields (so, say, the same field multiple
times) then I think there are at least two routes available for you:

 1. have a single-input field (or 2-3 inputs) and set it to "Multiple"
 2. create one big structured CCK data type of 50 fields.

The two will probably have different performance issues because of the way
they're stored. In the first instance, the table has a single-celled row
(plus a cell for row id/delta, and a cell for node id) per input field:
this means that creating the single node involves bringing in 50 rows in
the SQL.

In the second instance, the data table has a 50-celled row per node: this
means that any time you want a small bit of the information in a view, CCK
will prompt the views module to get it all;  my guess is that this would
slow down the view more, but that the view would be slow in either case if
you can't avoid grabbing all 50 inputs. It would also improve matters
because you don't have 50 row IDs and 50 node IDs.

But you might want to benchmark both for your huge data sizes and see
which is the greater. For such a lot of data you really do want to be
peeking under the Drupal hood anyway, as there's bound to be SQL
optimizations you can do. The devel module can help you with creating
large amounts of dummy content for benchmarking. You could also think
about rewriting the SQL using hooks if you're feeling really adventurous.
Probably you could trick your CCK module into returning a restricted
number of columns in the latter case, when you're in a view mode.

[plug] If you want to know how to create a big internally-structured CCK
field, I've got an example module that I built recently for storing
the equivalent of "Amazon book formats" i.e. rich data of
DxWxH+description+example image, which can then be multiple to show how
many different formats - paperback, hardback etc. - a book can come in.

http://www.jpstacey.info/blog/2007/09/20/a-complex-cck-module-in-drupal/

The D,W,H,descr and image data are all stored in separate cells, one "book
format" per row. So for ten nodes of six formats, you have a 5+2-column,
60-row table.

Cheers,
J-P