Is metadata necessary to have

[Paula66]

Is metadata.db necessary to have in a folder for calibre to recognize it as a library? I installed the calibre app on another hard drive and tried alot of different ways to get calibre to recognise the books I had moved to this drive. The only success I had and it was not with that folder of books but an older folder that I had sent to this hard drive as a back up, was with a my kindle content folder, with a calibre library in it.
If I have metadata.db from a different calibre library can I copy it to another library without it changing any of the content in that library. If I hadn't had a sugarsync capacity I would have lost 50% of my books through my blind belief that my first or second attempt had worked.
If this is a stupid question I am sorry I am just baffled by my lack of success with what I thought would be an easy move.

[theducks]

Originally Posted by Paula66

Is metadata.db necessary to have in a folder for calibre to recognize it as a library? I installed the calibre app on another hard drive and tried alot of different ways to get calibre to recognise the books I had moved to this drive. The only success I had and it was not with that folder of books but an older folder that I had sent to this hard drive as a back up, was with a my kindle content folder, with a calibre library in it.
If I have metadata.db from a different calibre library can I copy it to another library without it changing any of the content in that library. If I hadn't had a sugarsync capacity I would have lost 50% of my books through my blind belief that my first or second attempt had worked.
If this is a stupid question I am sorry I am just baffled by my lack of success with what I thought would be an easy move.

Metadata.DB is the Library you see on the screen.
It needs to be precisely in synch with the folders in the same library.
That is why you should never mess around inside the Library Folder. One tiny change and calibre may 'lose track' of the book (the book may be there, Calibre just does not know it)

[Paula66]

But why did a problem occur if I moved the entire folder and contents. Shouldn't the metadata.db have moved with the folder? It was when the folder (with the metadata.db) wasn't foundthat I started having trouble.
Also if the metadata.db is the library then why does it not find anything when it is pointed at the metadata.db
Sorry going off track.
I need to find a way of adding a second library to calibre safely that was once a subfolder of the my kindle content folder Will the metadata be in that folder already or has something happened when i have moved it out of the my kindle content folderto an external drive
Thank you for your fast response I really appreciate your help. i know I am struggling thank you.
Please understand that any instructions will have to be precise. I can find many different meaning in a sentence. lol

[BetterRed]

@Paula66 - try this

1. start calibre
2. click the Library button
3. select Switch/Create Library
   
4. ensure the Use the previously existing library at the new location option is selected
5. enter or navigate to the New location
6. click OK

You will notice that dialogue has an option to move a library, you 'should have used' that to do the move. However, providing I've understood the problem correctly, then the above should solve your problem

Calibre maintains a list of the libraries it knows about, including their locations. If it didn't then users would have to tell it which library and where every time they used the program. If you move or rename a library 'outside' of Calibre then you have to tell Calibre after the the event that you 'did it'. That's why its preferable to let Calibre 'do the work' of moving, renaming etc.

BR

[theducks]

Originally Posted by Paula66

But why did a problem occur if I moved the entire folder and contents. Shouldn't the metadata.db have moved with the folder? It was when the folder (with the metadata.db) wasn't foundthat I started having trouble.
Also if the metadata.db is the library then why does it not find anything when it is pointed at the metadata.db
Sorry going off track.
I need to find a way of adding a second library to calibre safely that was once a subfolder of the my kindle content folder Will the metadata be in that folder already or has something happened when i have moved it out of the my kindle content folderto an external drive
Thank you for your fast response I really appreciate your help. i know I am struggling thank you.
Please understand that any instructions will have to be precise. I can find many different meaning in a sentence. lol

Betterred gave you the recommended way to move a library and Yes, copying the entire folder should work in most cases.

The not in most cases can happen if you copy a Library from a case insensitive OS like XP to one that is (or has a variant in the way long file names are stored) like Linux. 'My Book' is not the same as 'my book' to OS like Linux (an Yes, bot can exist in Linux and accessing the same Library (via Windows mounted share) will have trouble because you have 2 files, but Windows only can see one and will trip if it tries to write to/delete it .

[Paula66]

Thank you both so much for all your help. I was getting quite stressed. I will never move a calibre library again without using calibre.