Duplicate/Copy column

[Smokva]

Is there a way to duplicate or copy a non-user defined column?
I have a large library and my TAG columns are a real mess. I would like to clean them up but it will take a while. In the mean time, I don't want to delete the existing tags as they would be useful in until the update is complete,
My first thought was to create a user-defined column called 'My Tags' and use it to represent the new organized tags. However, what I really want is the original TAG column to have the updated tags. So if I do this, I have to find a way to copy/overwrite the data in 'My Tags' into the original 'Tags' once its complete. I have no idea how to do that.
My second thought was to duplicate the original TAGS column, and then simply erase the data in the original TAG column and add the new tags directly using the copied column as reference. When I am finished, I would simply delete the other column. However, I have no idea how to duplicate the column.

Any advice would be appreciated.
(Note: Please don't say just to use the new column 'My Tags'. I know that is an option, but if I export or transfer books, the other user would have to have that column in order for the data to transfer. Everyone automatically has the TAG column, so that is why I want that original column to have the updated data.

Thanks in advance!

[eschwartz]

Select all books you want to affect, hit Edit Metadata. Now, in Bulk Edit Metadata, use the third tab (Search and Replace) to search the tags column and replace into the #custom_mytags column.

You will need the following settings:

Search Mode: Regular Expression
Search Field: tags
Search for: (.*)
Replace with: \1
Destination Field: #custom_mytags


This will copy the contents of the tags column for all books, into the new column. Once they are cleaned, you can simply repeat the same S&R, but switch the Search and Destination fields around, to copy in the other direction.


Do remember though -- when doing bulk changes, be careful not to jump the gun! There is NO going back, unless you have backed up your library!
You can seriously mess up your library and delete things permanently if you are not careful.
/end boilerplate warning

[BetterRed]

Originally Posted by Smokva

Is there a way to duplicate or copy a non-user defined column?
I have a large library and my TAG columns are a real mess. I would like to clean them up but it will take a while...

@Smokva - and/or you might want to have a look at this plugin ==>> QuarantineAndScrub. I believe it's purpose is to take the burden out of cleaning up metadata such tags.

BR

[Smokva]

@eschwarts: Thank you very much. This worked great. Between the backup and the copying, it took some time (like I said... lots of books ) but it duplicated well, and I am able to delete sections of the original TAG column without it affecting the MY TAGS column. Just what I was looking for. I assume (.*) and \1 are variations of 'copy all' and 'paste all' respectively.
And thank you for making your instructions idiot proof. I appreciate that you did not say "Just use search and replace!"

@Better Red: Thanks for the suggestion. I actually did look at that plug-in before posting but it seemed that there were too many possible pitfalls for me to use it successfully at my current level of expertise (or lack thereof). Even the programmer warned against it ... and being a firm believer in Murphy's Law.... well, need I say more?
I mean, I am still trying to figure out what the heck "Library Metadata Backup Status" in Library maintenance refers to. (Its obviously not a back-up bc that is done by copying the file through Explorer, so what the heck does it do?)
But at some point in the future, I will experiment with it and/or other plug-ins. There are some good ideas there. At this point though, I just want to get the job done.
Thanks again to both of you for the quick response.

[eschwartz]

Originally Posted by Smokva

@eschwarts: Thank you very much. This worked great. Between the backup and the copying, it took some time (like I said... lots of books ) but it duplicated well, and I am able to delete sections of the original TAG column without it affecting the MY TAGS column. Just what I was looking for. I assume (.*) and \1 are variations of 'copy all' and 'paste all' respectively.
And thank you for making your instructions idiot proof. I appreciate that you did not say "Just use search and replace!"

You're welcome. And yes, they are the Regular Expressions way of saying "capture all" and "replace all".
(Follow that link if you are interested in reading the calibre manual page on Regular Expressions. Useful tool, although of course not obligatory. )

@Better Red: Thanks for the suggestion. I actually did look at that plug-in before posting but it seemed that there were too many possible pitfalls for me to use it successfully at my current level of expertise (or lack thereof). Even the programmer warned against it ... and being a firm believer in Murphy's Law.... well, need I say more?
I mean, I am still trying to figure out what the heck "Library Metadata Backup Status" in Library maintenance refers to. (Its obviously not a back-up bc that is done by copying the file through Explorer, so what the heck does it do?)
But at some point in the future, I will experiment with it and/or other plug-ins. There are some good ideas there. At this point though, I just want to get the job done.
Thanks again to both of you for the quick response.

Well, I can't help you with that plugin (it confused my cursory inspection as well) but regarding the backup status, that refers to the backup metadata.opf files in each ebook folder. They contain plaintext structured references to all the metadata about each book. You can ignore them, unless the database tragically corrupts itself someday, and you need to use the Restore Database feature.
And even then, you just click the button and calibre worries about the .opf files.

[BetterRed]

@Smokva - no worries,

Some metadata updates cascade through many books - eg if you changed a Publisher name from Random Hose, to Random House then all the books with Random Hose would have their metadata updated. In the book folders you'll see there are metadata.opf files, the sole purpose of which is to backup the metadata, for use by the Restore database function. The metadata.opf files are not written immediately something changes, they are written in a background task at about 1/second - so if you had 1,000 Random Hose books it would take about 15 minutes to write the 1,000 updated metadata.opf files with Random House.

The "Library Metadata Backup Status" tells you how how many metadata.opf files are still waiting to be written. Don't worry... if you close calibre, it will carry on rewriting them when calibre is started again. If you want to get it done quickly, use the calibredb backup_metadata command. I did something the other day that would have taken more than 2 hours to write the new files, it took about two minutes from the command line - the reason I did it is that the disk ticking annoys me.

BR

[Amalthia]

Originally Posted by eschwartz

Select all books you want to affect, hit Edit Metadata. Now, in Bulk Edit Metadata, use the third tab (Search and Replace) to search the tags column and replace into the #custom_mytags column.

You will need the following settings:

Search Mode: Regular Expression
Search Field: tags
Search for: (.*)
Replace with: \1
Destination Field: #custom_mytags

Thanks for sharing how you did this! My method was too slow.

[Ealdwulf]

Originally Posted by eschwartz

You will need the following settings:

Search Mode: Regular Expression
Search Field: tags
Search for: (.*)
Replace with: \1
Destination Field: #custom_mytags

Bit of a necro here, but this was exactly what I needed to replace the tags on my books with what I have identified by a Genre column.

Thank You!