Search for book in top category only

[groob]

Hello,
I have a custom category `genre` that contains sub categories, for example:

entertainment
entertainment.comicbook
entertainment.humor
entertainment.music
entertainment.storytelling
entertainment.television
entertainment.writing

Now, how can I find out all the books that belong to the `#genre:"=entertainment"` top level only?

Meaning all the books that have an assigned category `entertainment` BUT NONE of the subcategories of `entertainment`?

I have tried this search but it doesn't work:

#genre:"=entertainment" AND NOT #genre:"=.entertainment"

Even if there is a book with just the top level `entertainment` applied with none of the subcategories the results are empty

Any idea?

[chaley]

Use the tag browser to see what the search expressions are. For example, click on the "entertainment" genre until you see a green single + sign then look at the search bar.

For more information see "‘Equality’ searches" in "The search interface" in the calibre manual.

[groob]

Originally Posted by chaley

For example, click on the "entertainment" genre until you see a green single + sign then look at the search bar.

I know, that produces

#genre:"=entertainment"

What I don't know is how to search for sub-categories only. Because this

#genre:"=.entertainment"

(notice the dot) will search entertainment and all its subcategories.

[chaley]

Originally Posted by groob

Now, how can I find out all the books that belong to the `#genre:"=entertainment"` top level only?

Originally Posted by groob

I know, that produces
What I don't know is how to search for sub-categories only. Because this

Those are not the same question.

What exactly do you want to do?

[chaley]

If your second post is the question you are asking, then this

#genre:"=.entertainment" and not #genre:"=entertainment"

or this

#genre:"~^entertainment\."

[groob]

Originally Posted by chaley

If your second post is the question you are asking, then this

#genre:"=.entertainment" and not #genre:"=entertainment"

or this

#genre:"~^entertainment\."

Thanks for your help,
I'll try to be more clear:
- I have some books that have the top category only, and some books that have the top category AND any of the subcategories.
- I need to search which books having the top category don't have any additional subcategories assigned.

So logically it would be: lookup the top category only AND exclude any subcategory, but again, my example and also your examples do not work.

To me this should be correct:

#genre:"=entertainment" AND NOT #genre:"=.entertainment"

but it's not.

[DNSB]

Something like this with the '.' moved after entertainment?

#genre:"=entertainment" AND NOT #genre:"=entertainment."

What does a simple sort on the genre column show since entertainment should sort ahead of entertainment. ?

[chaley]

Originally Posted by groob

Thanks for your help,
I'll try to be more clear:
- I have some books that have the top category only, and some books that have the top category AND any of the subcategories.
- I need to search which books having the top category don't have any additional subcategories assigned.

So logically it would be: lookup the top category only AND exclude any subcategory, but again, my example and also your examples do not work.

To me this should be correct:

#genre:"=entertainment" AND NOT #genre:"=.entertainment"

but it's not.

That is question #1 again.

This search, produced by the tag browser when the single green plus is showing

#genre:"=entertainment"

finds all books with the genre "entertainment" but no subgenres of entertainment.

Examples:

• Only the top level genre entertainment. Note that the number of books shown, 1, equals the count in the total count of the category minus the sum of the count of the children:
  
• The top level and all its children. The number of books, 13, equals the total on the top level item:
  
• Only the children. This search combines the 2 above searches. The count, 12, equals the sum of the counts of the children:
  

[chaley]

Originally Posted by groob

Thanks for your help,
I'll try to be more clear:
[...]

I realized I misunderstood your posts. My apologies. And sorry for being super pedantic in this post. I am "thinking out loud".

To rephrase the question using sets, what (I think) you want is the intersection of two sets

top_level_set ⋂ ~set_of_children

where

• top_level_set is the books that contain the bare (top-level) genre "entertainment".
• set_of_children is the books that contain children of "entertainment".

Computing top_level_set is easy using the search

#genre:"=entertainment"

Computing set_of_children is more problematic. As you noted, the search

#genre:"=.entertainment"

can't be used for set_of_children because the search builds the set

(top_level_set ∪ set_of_children)

The expression

top_level_set ⋂ ~(top_level_set ∪ set_of_children)

is the empty set.

We must find a search that finds children of entertainment, ignoring entertainment itself. The regexp search in post #5 and alluded to by @DNSB in post 7

#genre:"~^entertainment\."

builds set_of_children by finding the set of books where "entertainment" is followed by a period.

Putting the two together, the search

#genre:"=entertainment" AND NOT #genre:"~^entertainment\."

builds the intersection we want

top_level_set ⋂ ~set_of_children

These screen captures shows that the search works. The first shows the books without a search. The second shows the books after applying the search.