Custom Columns Questions

[Rellwood]

Any ideas on how to create a column that keeps track of changes in other columns? A comment (long text) column that keeps track of each date change in a date column, or tag change in others?

Also, is there a suggestion on how to set up a number column that changes per change in another column?

The primary goal is keeping track of read dates, and times read. I have the "latest read date" column, but as I change from one date to another per read, the previous date is removed and I lose track of both it, and the read count.

Having a column set up to keep track of the dates and having a number column increase with each change would be great. However, it isn't a huge deal for the number column, but having a column in general that keeps a tab of every change in another column whatever it may be (tags, dates, etc.) would really be useful.

Actually, to clarify, I am not looking to keep track of changes per se, but more like keeping all the information available even after it changes. A comma separated column would be great to do as well.

[davidfor]

I don't know what made me think of this, but it occurs to me, that you might be thinking of this the wrong way around. Or, that it might be easier to do the other way.

Your idea is to have some way were when you change the value in a column, the previous value is appended to the value in another column. But, you can do it the other way without a plugin or other changes to calibre.

If you maintain the column with the list of values, you can have another column that displays the last entry in the list. And as you are interested in the number of times you have read the book, you could have another column that shows the count of the entries.

Another way to do this is via Goodreads. They recently changed things so you could record each time you start and finish a book. Each time you add the book to the "currently-reading" shelf it is marked as started, and when you add it to the "read" shelf it is marked as finished. The Goodreads Sync plugin can do the updating as you go along. Or you can go to Goodreads to record your previous reads.

[Rellwood]

@davidfor

I never knew that moving a book from the "currently reading" column to the "read" column would change the read count. I always assumed that I had to manually go in and add the extra read dates via edit. I guess this qualifies as one of the new changes you referred to. I tend to just forgo that column all together and just move the book from whatever original column it's in to the read column via Calibre and have the automatically uploaded read date enabled.


I can get the read count in their downloaded csv of my library, but the various dates read per book is not listed. I tend to do a lot of re-reading and it's nice to keep track of each re-read date. But there isn't a sync feature on the plugin that keeps track of each read date, just the "updated" date (which is a really nice feature).

I guess I really need to learn how to create decent custom columns, for the life of me, I cannot get the language. I know there is a way to create a column that keeps track of the changes in others, via appending, but does this work in date columns? Will the changes move to a text column or a tags column? Again, this requires more education.

Thank you so much for giving me more to think about and another way to approach this dilemma!

[davidfor]

Originally Posted by Rellwood

@davidfor

I never knew that moving a book from the "currently reading" column to the "read" column would change the read count. I always assumed that I had to manually go in and add the extra read dates via edit. I guess this qualifies as one of the new changes you referred to. I tend to just forgo that column all together and just move the book from whatever original column it's in to the read column via Calibre and have the automatically uploaded read date enabled.

I can get the read count in their downloaded csv of my library, but the various dates read per book is not listed. I tend to do a lot of re-reading and it's nice to keep track of each re-read date. But there isn't a sync feature on the plugin that keeps track of each read date, just the "updated" date (which is a really nice feature).

I think these are comments about Goodreads rather than calibre itself. They always had a read count and the start and finish date for the last time you read it. I don't know if they automatically increment the read count as I haven't reread a book since this feature was added.

I guess I really need to learn how to create decent custom columns, for the life of me, I cannot get the language. I know there is a way to create a column that keeps track of the changes in others, via appending, but does this work in date columns? Will the changes move to a text column or a tags column? Again, this requires more education.

I don't do enough with the template language to get used to it and have to look it up each time. For the columns, I think you would need to use a text column for the list of dates and just treat them as a text.

[Terisa de morgan]

Originally Posted by davidfor

I think these are comments about Goodreads rather than calibre itself. They always had a read count and the start and finish date for the last time you read it. I don't know if they automatically increment the read count as I haven't reread a book since this feature was added.

Yes, they do.

[Rellwood]

Originally Posted by davidfor

I think these are comments about Goodreads rather than calibre itself. They always had a read count and the start and finish date for the last time you read it. I don't know if they automatically increment the read count as I haven't reread a book since this feature was added.


I don't do enough with the template language to get used to it and have to look it up each time. For the columns, I think you would need to use a text column for the list of dates and just treat them as a text.

I understand that the read count is a Goodreads question. Regarding the template language to treat the date as text, that is what I am trying to do. I am attempting to take a date column already set up (latest date read) and have that data go into another text column that won't erase each time the latest date read column changes. So far the best I can come up with is the column built from other columns but treated like text. I still can't get the dates to stay in that column after changing the original.

Does this make sense?

I simply want a column that keeps track of and doesn't erase data that came from another column. There are no date columns that can be treated like text.

I'll go back to the user manual to see if there is anything in it to help me out.

[BetterRed]

@rellwood - maybe this will work.

Add a custom column of type Column built from other columns with a template that formats the date as year, month and day (e.g. 2017-05-01), then in Bulk MDE Search and Replace append that column to a Tag like custom column. Tag like columns can have multiple values, won't allow duplicates, and will display the values in a sensible order.

I'll leave you to work out the custom column template and the Bulk MDE S&R spec (once you have one that works you can save it for later reuse). IIRC the manual has some examples for dealing with dates in templates, and the Mode parameter in Bulk MDE S&R has an Append option.

BR

[theducks]

The Template Language has:
format_date(val, format_string) – format the value, which must be a date field, using the format_string, returning a string. The formatting codes are:
YYYY

See https://manual.calibre-ebook.com/template_lang.html