When running in Node.js, OurBigBook dumps the IDs of all processed files to a out/db.sqlite3 file in the out directory, and then reads from that file when IDs are needed.
When converting under a directory that contains ourbigbook.json, out/db.sqlite3 is placed inside the same directory as the ourbigbook.json file.
If there is no ourbigbook.json in parent directories, then out/db.sqlite3 is placed in the current working directory.
db.sqlite3 is not created or used when handling input from stdin.
When running in the browser, the same JavaScript API will send queries to the server instead of a local SQLite database.
To inspect the ID database to debug it, you can use:
sqlite3 out/db.sqlite3 .dump
It is often useful to dump a single table, e.g. to dump the ids table:
sqlite3 out/db.sqlite3 '.dump ids'
and one particularly important query is to dump a list of all known IDs:
sqlite3 out/db.sqlite3 'select id from ids'
You can force ourbigbook to not use the ID database with the --no-db command line option

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