How Date Modified column works

[LadyKate]

I made some changes to the custom columns this evening. I did not make any modifications to the Modified column.

Now every book in my library has the Modified date set to today.

I noticed when I upgraded Calibre the Modified date changed.

Is this the way it is supposed to be?? I tend to go by the modified date to determine what books need to be copied over to my tablet.

[DaltonST]

Yes. For that reason and others the "Job Spy" plug-in has GUI Tools to allow you to back up and restore and/or manually change Date Modified.

DaltonST

[BetterRed]

@LadyKate - whenever you add, change or remove a custom column to a library the modified date for every book in the library is changed to 'Now'. AFAIK it's been ever thus. If you correct an Author or Publisher's name (etc, etc) then every book with that Author or Publisher name will have it's 'modified' date set to 'now'. If you enter a value into an authors Link field, then the modified date for all of the authors books are updated.

I maintain a separate 'last_change' custom column - I update it when I do something to a book that I regard as significant.

BR

[theducks]

All of the above

When something that caused Date Modified update to happen, you will also notice that there is a new metadata.opf being queued or written (right click Library Icon: Library Maintenance: Library Metadata Backup Status: ,non-zero number shows>

[DaltonST]

Also, if you do not want every book to be queued for an automatic metadata.opf backup, simply run the Job Spy GUI Tool named "Purge metadata.opf Backup Queue".

For actions that cause that to occur without restarting Calibre, you can click that Tool immediately. For others, such as changing Custom Columns in Preferences that requires a restart of Calibre, you can click that Tool as soon as Calibre restarts. A few might slip through, but better a few than tens of thousands of undesired metadata.opf updates that you find to be unnecessary and undesirable.


https://www.mobileread.com/forums/sho...d.php?t=269911



DaltonST

[chaley]

Note that if you use Calibre Companion, resetting the modified date back in time will break CC's metadata syncing. Also note that if you don't let calibre write the OPF files and if you need to do a database recovery then you might get the wrong metadata values.

[LadyKate]

Originally Posted by BetterRed

@LadyKate - whenever you add, change or remove a custom column to a library the modified date for every book in the library is changed to 'Now'. AFAIK it's been ever thus. If you correct an Author or Publisher's name (etc, etc) then every book with that Author or Publisher name will have it's 'modified' date set to 'now'. If you enter a value into an authors Link field, then the modified date for all of the authors books are updated.

I maintain a separate 'last_change' custom column - I update it when I do something to a book that I regard as significant.

BR

You manually update the 'last_change' column?

I was just wondering if I had something set weird. I'd kind of noticed it before but hadn't realized that adding a column changed the date.

Thanks all for the responses!

[JSWolf]

Originally Posted by DaltonST

Also, if you do not want every book to be queued for an automatic metadata.opf backup, simply run the Job Spy GUI Tool named "Purge metadata.opf Backup Queue".

For actions that cause that to occur without restarting Calibre, you can click that Tool immediately. For others, such as changing Custom Columns in Preferences that requires a restart of Calibre, you can click that Tool as soon as Calibre restarts. A few might slip through, but better a few than tens of thousands of undesired metadata.opf updates that you find to be unnecessary and undesirable.


https://www.mobileread.com/forums/sho...d.php?t=269911



DaltonST

The OPF file exists so if for some reason the Calibre database becomes corrupted, you can create a new one using the OPF files. Giving people the ability to delete the OPF files easily or by mistake is a bad idea. I suggest you remove that feature from the Job Spy plugin so the only way to delete the OPF files is by hand meaning it has to be done on purpose. What some will think is that it's a good way to free up disk space and then if anyone needs them, they won't be there.

Please don't add features to your plugins like this that are a bad idea. If there are any other such bad features in any of your plugins, please remove them as well.

[BetterRed]

Originally Posted by LadyKate

You manually update the 'last_change' column?

I was just wondering if I had something set weird. I'd kind of noticed it before but hadn't realized that adding a column changed the date.

Thanks all for the responses!

Yes - I usually change two columns, Last Change Date to Now, and Status to one of the allowable values, and if necessary I add some text to Notes which is a long text column. I edit metadata in the book list, those three columns are adjacent so I can tab from one to the next and remain in Edit mode. Press '=' to set a date to Now, '-' to clear it.

BR

[theducks]

If you make a change via 'under the skirts' Calibre has no mechanism to know a non-calibre process made a change. the burden becomes yours to update last_modified (if you care )

[LadyKate]

Originally Posted by theducks

If you make a change via 'under the skirts' Calibre has no mechanism to know a non-calibre process made a change. the burden becomes yours to update last_modified (if you care )

I don't tend to go :under the skirts: except to open the folder and pull a newly added or duplicate ebook to an existing but not as good version that does have better metadata filled in.

But I did just notice that when I upgraded Calibre today the "Modified" date didn't change.

[BetterRed]

@LadyKate - if you want to replace an existing format file, it is better to drag it from wherever it is and drop on the book details panel (where the cover is). It will overwrite the existing format file, update the size in the database, and do any other housekeeping Kovid deems necessary. The file you dragged-dropped remains in place - even if it is on the same drive. Much safer and you won't be chastised for 'going under the covers/skirts/kilts etc'

BR

[theducks]

@LK
Or drop it into the 'Formats' section of the Metadata editor.
no need to keep a precise file name in either BR's or this way

Rare is the need to go under the skirts

[LadyKate]

Originally Posted by BetterRed

@LadyKate - if you want to replace an existing format file, it is better to drag it from wherever it is and drop on the book details panel (where the cover is). It will overwrite the existing format file, update the size in the database, and do any other housekeeping Kovid deems necessary. The file you dragged-dropped remains in place - even if it is on the same drive. Much safer and you won't be chastised for 'going under the covers/skirts/kilts etc'

BR

Um that is how I do it. By under the skirts I mean I open the calibre record containing newly added book and open the file folder then drag the book format I want to the old record with good metadata added (then if it is an arc I'm replacing, modify the tag to remove arc)