hierarchy feature using rough "Dewey number" instead of "genre" - multiple DDCs?

[kite]

Dewey Decimal Code = DDC

I think I have made a hierarchical structure, following "Managing subgroups of books, for example “genre”", but using Dewey hundreds, then Dewey tens and occasionally Dewey single digits. So 500.550.551 is where Global Warming books go. And 400.490 is for Egyptian Hieroglyphics.

This all works nicely, with access to the DDC subgroups in the left pane below the tags, or in a column in the books display area.

But.
When I try to have two or more Dewey codes for a single book then the codes are not treated separately but instead all just put in a continual sequence.
So 100, 200 is just treated as being a special category of the 100 subgroup. And the book doesn't show with the other DDC 200 books.

The tutorial says that multiple genres are possible for a single book. Is the problem that I am using numbers rather than letters for places in the hierarchy?

It looks to me like I am not using the correct separator between the codes. I have tried commas and spaces so far.

Any help appreciated.

[chaley]

The custom column you created is probably not "Comma separated text, like tags ...", but is instead "Text ...". The first type lets you put multiple values in the column. The second treats the contents as one value.

[kite]

Hi chaley, thank you, you've identified the problem.

How can I change the "Column Type" setting of my existing Custom Column to "Comma separated text, like tags ..."?
(If I go Preferences>Interface/Add Your Own Columns>i/"edit settings of a user defined column", then "Column type: Text, column shown in tag browser" is greyed out and inaccessible.)

If I can't change the settings of the existing Custom column, how can I transfer the Dewey values across to a correctly set-up Custom Column?

[BetterRed]

Originally Posted by kite

how can I transfer the Dewey values across to a correctly set-up Custom Column?

@kite - you can use Bulk Metadata Edit->Search and Replace tab.

Careful though, you can break things with S&R, back up your library and test on few books - you can save and reuse S&R settings (v. handy)

BR

[theducks]

BR had it

Make the new column
then use the Bulk mode S&R to reformat (if needed) and COPY

Source field: <the old>
(search mode: REGEX)

Search: (.+)
Destination field: <the new>
Replace with: \1

Assumes comma between values
Provide samples if other and REGEX help needed