How to see files of a particular tag in org-roam?

Question

Before I installed org-roam I saw a screenshot or a video somewhere in which the tags of an org-roam note looked like links. I was under the impression that org-roam allows you to see all notes of a particular tag.

I added a tag to my test note, but I don't see a way to see all notes with that tag. I also could not find any hints on that in the org-roam User Guide.

How can I see a list of all notes with a particular tag (ideally as a list of links so that I can click on a note to navigate to it)?

Answer 1

You can search by tag by running org-roam-find-file. The tags will be displayed in brackets next to the titles of the files.

To see a list of files as you type, set org-roam-completion-system to 'ido.

(setq org-roam-completion-system 'ido)

Alternatively,

• install Ivy and enable ivy-mode, or
• install Helm and enable helm-mode.

Ido, Ivy, and Helm are all completion systems.

Additional reading about completion systems

• See Mastering Emacs - Introduction to Ido Mode for an (in-depth) introduction to Ido as a completion system. Some excerpts:

  • A description of builtin "completing-read", the prompt that you're seeing:

  [...] if you were to search for the buffer “*Customize Group: Foobar*” without Ido you’d have to contort your fingers and type the *, then TAB (and hope it completes) and if not, type in some more; then rinse and repeat.

  • Describing Ido:

  With Ido you’d type a few characters until you find the match, or until you narrow down your list of matches to a manageable subset, and then press RET. Even better, with fuzzy matching you can find things even more efficiently. So the above buffer name could be found by typing “cgf” – c for Customize, g for Group and f for Foobar.

• See Helm Wiki#General concept for what Helm is in addition to just being a vertical Ido.

  People often think helm is just something like ido but displaying completion in a vertical layout instead of an horizontal one, it is not, helm is much more powerful than that.

• See Ivy Manual#Introduction

  Ivy is for quick and easy selection from a list. When Emacs prompts for a string from a list of several possible choices, Ivy springs into action to assist in narrowing and picking the right string from a vast number of choices.

Answer 2

If you want the node search to only display nodes with a specific tag, org-roam-node-find accepts a filter function as its third argument. This is covered incidentally in a video by System Crafters. The code from that video is:

(defun my/org-roam-filter-by-tag (tag-name)
    (lambda (node)
        (member tag-name (org-roam-node-tags node))))

(defun my/org-roam-find-project ()
    (interactive)
    ;; Select a project file to open, creating it if necessary
    (org-roam-node-find nil nil
        (my/org-roam-filter-by-tag "Project")))

Answer 3

The hack to enter org-roam tags linking them to empty files has been deprecated in org-roam since the addition of #+ROAM_TAGS

Instead, try adding a line such as #+ROAM_TAGS: tag1 tag2 tag3 tag4 to an org-file to your org-roam-directory.

Then, rebuild the cache using M-x and org-roam-db-build-cache. Now your completion system (ido, helm etc.) will be able to display the tags inside brackets when using org-roam-find-file.