Chapter 7: Tags and Properties - The Metadata Layer

Don’t type them manually. Press C-c C-c on a heading:

1. Org prompts: Tags:
2. Type tag names (with completion if configured)
3. Press Enter

Or use C-c C-q for the same effect (mnemonic: “q” for taQ).

Tags are case-sensitive. :Work: and :work: are different. Choose a convention and stick with it (lowercase recommended).

By default, tags inherit. A child heading has all its parent’s tags:

#+begin_example

#+end_example

“Design phase” effectively has tags :work:client_a:design:. “Development phase” has :work:client_a:development:. You don’t repeat common tags—inheritance handles it.

Disable inheritance if needed:

(setq org-use-tag-inheritance nil)

Or disable for specific tags:

(setq org-tags-exclude-from-inheritance '("project" "personal"))

Typing tags gets tedious. Predefine common ones:

(setq org-tag-alist '(("work" . ?w)
                      ("personal" . ?p)
                      ("urgent" . ?u)
                      ("email" . ?e)
                      ("phone" . ?h)
                      ("meeting" . ?m)))

Now when you press C-c C-c to add tags, Org shows a selection interface. Press w for “work”, u for “urgent”, etc. Much faster than typing.

Group related tags:

(setq org-tag-alist '((:startgroup . nil)
                      ("@office" . ?o)
                      ("@home" . ?h)
                      ("@errands" . ?e)
                      (:endgroup . nil)

                      (:startgroup . nil)
                      ("urgent" . ?u)
                      ("someday" . ?s)
                      (:endgroup . nil)))

Groups are mutually exclusive. Adding @office removes @home and @errands. Perfect for context tags (GTD-style).

Set tags available in specific files:

#+TAGS: work(w) personal(p) urgent(u)
#+TAGS: { @office(o) @home(h) @errands(e) }

The {} creates a mutually exclusive group (same as :startgroup: in elisp).

Apply tags to the entire file:

#+FILETAGS: :project_alpha:confidential:

Every heading in the file inherits these tags. Useful for project-specific files.

C-c / m - Show headings matching tag query

Examples:

• work - All headings tagged “work”
• work+urgent - Both “work” AND “urgent”
• work|personal - Either “work” OR “personal”
• work-boss - Tagged “work” but NOT “boss”
• work+urgent-meeting - Work AND urgent, but NOT meeting

The document folds to show only matches. Combined with tag inheritance, this is phenomenally powerful.

From the agenda (covered in Chapter 8):

C-c a m - Match tags across all agenda files

Your entire Org system becomes searchable by arbitrary tag combinations.

C-c C-x p - Set a property

Org prompts for property name, then value. The property drawer auto-creates if needed.

Some properties have special meaning:

• EFFORT - Time estimate (used in agenda views)
• CATEGORY - Category for agenda display
• ORDERED - If t, children must be completed in order
• CUSTOM_ID - For stable linking (Chapter 5)
• ID - Unique identifier

Others are custom metadata you define.

Like tags, properties can inherit:

#+begin_example

#+end_example

If CLIENT is set to inherit, all subtasks automatically have CLIENT: ACME Corp.

Configure inheritance:

(setq org-use-property-inheritance '("CLIENT" "PROJECT_CODE"))

Or inherit all properties (be careful—this can slow down large files):

(setq org-use-property-inheritance t)

Constrain property values for consistency:

#+PROPERTY: ASSIGNED_ALL Alice Bob Carol Dave
#+PROPERTY: STATUS_ALL Open In-Progress Blocked Completed
#+PROPERTY: PRIORITY_ALL Low Medium High Critical

Now when setting these properties, Org offers completion from the allowed values. No typos, no inconsistent data.

In elisp:

(setq org-global-properties
      '(("ASSIGNED_ALL" . "Alice Bob Carol Dave")
        ("STATUS_ALL" . "Open In-Progress Blocked Completed")))

View properties as a table:

C-c C-x C-c - Enable column view

Org displays headings with their properties in columns:

ITEM              | ASSIGNED | EFFORT | STATUS
---------------------------------------------------
Implement feature | Alice    | 4:00   | In-Progress
Write tests       | Bob      | 2:00   | Open
Deploy            | Carol    | 1:00   | Blocked

Edit properties directly in the column view. Press q to exit.

Define which columns to show:

#+COLUMNS: %25ITEM %ASSIGNED %EFFORT %STATUS

Or globally:

(setq org-columns-default-format "%25ITEM %TODO %3PRIORITY %TAGS %EFFORT")

Column view transforms Org files into databases with editable spreadsheet views.

Create property summaries:

#+BEGIN: columnview :hlines 1 :id local
#+END:

Place cursor on #+BEGIN: line and press C-c C-c. Org generates a table from properties:

#+BEGIN: columnview :hlines 1 :id local
| ITEM              | ASSIGNED | EFFORT | STATUS      |
|-------------------+----------+--------+-------------|
| Implement feature | Alice    | 4:00   | In-Progress |
| Write tests       | Bob      | 2:00   | Open        |
| Deploy            | Carol    | 1:00   | Blocked     |
#+END:

Update properties and regenerate with C-c C-c. The table auto-updates.

Generate reports this way:

• Task assignment by person
• Effort summaries by project
• Status overviews

Plain text becoming a database before your eyes.

Tag/property search syntax (C-c / m or C-c a m):

+work-boss+CLIENT="ACME Corp"+EFFORT>2:00

Translation: Tagged “work”, not “boss”, CLIENT property equals “ACME Corp”, and EFFORT greater than 2 hours.

Operators:

• = - Equals
• <> - Not equal
• < - Less than
• > - Greater than
• <= - Less than or equal
• >= - Greater than or equal

For numbers, times, and dates. For strings, use =.

Regular expressions:

CLIENT={acme|widgets}

Matches CLIENT containing “acme” or “widgets”.

This is query language built into plain text.

(setq org-tag-alist '((:startgroup)
                      ("@office" . ?o)
                      ("@home" . ?h)
                      ("@computer" . ?c)
                      ("@phone" . ?p)
                      ("@errands" . ?e)
                      (:endgroup)

                      ("work" . ?w)
                      ("personal" . ?r)))

Tag tasks by where they can be done. Filter your task list by current context.

#+begin_example

#+end_example

All tasks inherit project context.

(setq org-tag-alist '((:startgroup)
                      ("@high_energy" . ?h)
                      ("@low_energy" . ?l)
                      (:endgroup)))

Tag tasks by required energy. When you’re tired, filter for low-energy tasks.

#+begin_example

#+end_example

Track budgets, phases, and allocation through properties. Report with column view.