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BetterRed · 05-13-2020, 05:54 PM

@Mountain343 - seeing as I sent you here, a brief explanation

The erroneous Tag value "Lost Angles" is not contained within every book record, it is held in a Tags table where each entry has a unique row number and a value. These row numbers are used to relate the Tag values to books records. If you change the value to "Los Angeles" the only thing that changes is that value in the relevant row in the Tags table, the unique number does not change. Hence the relationship between the book record and the Tags table remains valid.

IMO spending a few minutes familiarising oneself with calibre's data base schema via a tool such as DB Browser for SQLite is worth the effort. If you're not familiar with the concepts of relational databases, start with the default library. Of necessity the handling of custom columns is a more complex than the built-in columns.

Stay Safe

BR

05-13-2020, 05:54 PM	#16
BetterRed null operator (he/him) Posts: 21,826 Karma: 30277270 Join Date: Mar 2012 Location: Sydney Australia Device: none	@Mountain343 - seeing as I sent you here, a brief explanation The erroneous Tag value "Lost Angles" is not contained within every book record, it is held in a Tags table where each entry has a unique row number and a value. These row numbers are used to relate the Tag values to books records. If you change the value to "Los Angeles" the only thing that changes is that value in the relevant row in the Tags table, the unique number does not change. Hence the relationship between the book record and the Tags table remains valid. IMO spending a few minutes familiarising oneself with calibre's data base schema via a tool such as DB Browser for SQLite is worth the effort. If you're not familiar with the concepts of relational databases, start with the default library. Of necessity the handling of custom columns is a more complex than the built-in columns. Stay Safe BR