1 common library with multiple sub-libraries in different "root" folders

[uiuiii]

Hi all experts, I need the solution from the title, maybe someone has found a solution?

In fact, previously, I managed books in different libraries, i.e. Science, IT, Business, etc...

Since Calibre can neither be launched in multiple instance in order to display multiple libraries at the same time, nor having ability to display multiple libraries within 1 instance, I merge all libraries into 1, for easy searching, separated them with custom field 'Group' (like tag).

Now, the issue is, there are many books I do not always need. I keep some most useful books in laptop, but for other less important ones, I prefer to save them on external HD. With separated libraries, I can keep some libraries on external HD, rather all on my laptop. When merging so into 1 library, all files are within the same "root" folder of this library, which uses laptop HD's space, what I don't wish to.

Is there a way, to organize all books within 1 library (for searching, overview of comments, etc), but physically, the files location can be customized to be in different "root" folders (identified by class/group for instance), i.e. on external/network folders, while some of them can be locally on laptop (library's MD folder)?

Thanks for any idea...

[gbm]

Originally Posted by uiuiii

Hi all experts, I need the solution from the title, maybe someone has found a solution?

In fact, previously, I managed books in different libraries, i.e. Science, IT, Business, etc...

Since Calibre can neither be launched in multiple instance in order to display multiple libraries at the same time, nor having ability to display multiple libraries within 1 instance, I merge all libraries into 1, for easy searching, separated them with custom field 'Group' (like tag).

Now, the issue is, there are many books I do not always need. I keep some most useful books in laptop, but for other less important ones, I prefer to save them on external HD. With separated libraries, I can keep some libraries on external HD, rather all on my laptop. When merging so into 1 library, all files are within the same "root" folder of this library, which uses laptop HD's space, what I don't wish to.

Is there a way, to organize all books within 1 library (for searching, overview of comments, etc), but physically, the files location can be customized to be in different "root" folders (identified by class/group for instance), i.e. on external/network folders, while some of them can be locally on laptop (library's MD folder)?

Thanks for any idea...

Yes Virtual Librarys.
tutorial


bernie

[theducks]

FWIW
VL's use the same top level folder

You can not split a physical (top level) library location. You must really split the Library

[uiuiii]

Thanks Bernie & theducks!

VL is good using filter rule, I archieved previously with custom field.
But as theducks says, the root folder is the same.

I thought, maybe, if we can organize/customize the file structure per ....groups, i.e. folders per set of authors/titles subfolders... then in this case, I can use windows' mklink command to link the folders to somewhere else.

But this seems not possible currently. Hope for next release (maybe not, it seems not to be the strategy of Calibre file structure)

[BetterRed]

Originally Posted by uiuiii

... then in this case, I can use windows' mklink command to link the folders to somewhere else...

@uiuiii There's nothing to stop you creating a folder or file symlink (outside of any calibre library) that refers to a folder or file within a calibre library. But if the path to the library folder or file changes you will have to effect a repair. The path can change if any of the following occur (n.b. I may have missed something) :

• the library is moved or renamed;
• the author name is changed - metadata downloads can do this 'surreptitiously';
• the book title is changed - metadata downloads can do this 'surreptitiously';
• the book number is changed, I can't recall why this happens, but happen it does;
• the folder/file naming conventions embedded within calibre change, which has happened.

So I would advise against creating symlinks that reference calibre library folders and files.

BR

[uiuiii]

Thanks BetterRed. You're right, it will not work if we do it at book title/author level. That's why I mean to create a link per group of books, not per book, and that works, as long as the link is at the root folder/library level, not at the book level.

Currently, this solution works for me only per library, which I can, for instance, displaying 2 libraries at the same time, one with main instance of Calibre, and another with a 2nd Calibre via VMWare, pointing to libraries via either links or shares.

If we cannot have a folder per group, maybe in a future release of Calibre, there would be a VL which is not only a subset/projection of a library, but also a joint view/union of libraries? Is that possible, Goyal?

[Inferno]

Just an idea as space is the only issue and you want a "library" that is the sum of all your libraries. Lets call this one Catalog.

Make a merged version of your libraries while keeping the original libraries safe on your external drive. With the merged library (Catalog) temporarily taking most of your drive space, selecting all books delete the "epub" files using "remove files of a specific format from selected books". Repeat this process for mobi, azw, pdf etc.

This will leave you with a library that has only the metadata info and not the books.

You will need a field that indicates a book needs to be added to the catalog in your other libraries.

I forgot to mention that this catalog should be considered a "static" record of your other libraries. You should not update the metadata of the entries as the metadata of your books in their individual libraries will not be changed.

[uiuiii]

Thanks Inferno for the idea.

Uhm, yes, but then we will have a hard time to add book again.

In this case I think I could apply your idea, by maintaining 2 "complete" libraires, one on the external harddisc with all books, and another on laptop with also all MD, but this one has a VL filtering less important books to be deleted.

From there on, new book will be first added to both libraries, and optionally delete book format but not MD on the laptop's library.

This could be a solution for the moment. Thanks again Inferno!

[LadyKate]

If you do this you should keep in mind that running a check of the library will provide errors as it will not find the book files.