When an Org file containing org-roam notes is too large, it is necessary to move a subtree to an independent org-roam node file via the command org-roam-extract-subtree.

Caveats

  1. The node file must start with :PROPERTIES:, otherwise, it cannot be considered as an org-roam note. Then if the subtree has a timestamp such as CLOSED, this timestamp will appear on the first line, which invalidates the node file. Therefore, it should be manually removed.

  2. There should be no self-created properties, such as CREATED: <time-stamp> that I’ve used, otherwise only the node ID is in the org-roam database but nothing else. This can be verified by running org-roam-db-diagnose-node in the node file buffer and we only obtain something like this:

    #s(org-roam-node nil nil nil nil nil "80166ed4-1374-4bca-a647-6e0058b77717" nil 129 nil nil nil nil nil nil nil nil nil nil)

    After deleting the property and updating the database, the diagnosis returns meaningful results.

    #s(org-roam-node "/home/jihuan/文档/Documents/peabody/docs/org-notes/20241115180500-operator_preconditioning_in_bem.org" "Operator preconditioning in BEM" nil (26546 47291 830650 561000) (26546 47289 774607 292000) "80166ed4-1374-4bca-a647-6e0058b77717" 0 1 nil nil nil nil "Operator preconditioning in BEM" (("CATEGORY" . "20241115180500-operator_preconditioning_in_bem") ("ID" . "80166ed4-1374-4bca-a647-6e0058b77717") ("CREATED" . "<2024-11-15 Fri 18:05>") ("BLOCKED" . "") ("FILE" . "/home/jihuan/文档/Documents/peabody/docs/org-notes/20241115180500-operator_preconditioning_in_bem.org") ("PRIORITY" . "B")) nil nil nil nil)
  3. Similarly, there should be an empty line between the +title: line and the note contents, otherwise the above problem also appears.