# Custom org-id format **URL:** \ **Category:** Tips\ **Created:** [April 28, 2024, 10:55pm UTC](https://org-roam.discourse.group/t/custom-org-id-format/3448 "2024-04-28T22:55:21Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![akashp](https://yyz2.discourse-cdn.com/free1/user_avatar/org-roam.discourse.group/akashp/32/1383_2.png) [@akashp](https://org-roam.discourse.group/u/akashp)\ **Post date:** [April 28, 2024, 10:55pm UTC](https://org-roam.discourse.group/t/custom-org-id-format/3448/1 "2024-04-28T22:55:21Z")
Problem: Make org-id more human readable while ensuring uniqueness. Persistent daily counter – highjacking 'ts format. ```auto ;; org-id-counter - definition and infrastructure for org-id format %date-%counter (defvar org-id-counter (make-hash-table :size 1 :test 'equal) "Hash table to store the counter for each day.") (defvar org-id-counter-location (locate-user-emacs-file "org-id-counter")) (setq org-id-method 'ts) (defun org-id-counter-format () "Generate an Org ID using the format %Y/%m/%d-%counter." (let* ((today (format-time-string "%Y/%m/%d")) (counter (or (gethash today org-id-counter) 1)) (id (format "%s:%s" today (number-to-string counter)))) (puthash today (1+ counter) org-id-counter) id)) ;; iteration logic (defun org-id-counter-advice (&rest args) "Advice function to set `org-id-ts-format` before calling `org-id-new`." (setq org-id-ts-format (funcall #'org-id-counter-format))) (advice-add 'org-id-new :before #'org-id-counter-advice) ;; Persistent counter for the day (defun org-id-counter-save () "Save org-id-counter hash table to disk." (with-temp-file org-id-counter-location (prin1 org-id-counter (current-buffer)))) (add-hook 'kill-emacs-hook #'org-id-counter-save) ;; Save the hash table on Emacs exit (defun org-id-counter-load () "Load org-id-counter hash table from disk." (when (file-exists-p org-id-counter-location) (if (= 0 (nth 7 (file-attributes org-id-counter-location))) ; Check if file is empty (setq org-id-counter (make-hash-table :test 'equal)) ; Initialize with empty hash table (with-temp-buffer (insert-file-contents org-id-counter-location) (let ((data (read (current-buffer)))) (when (hash-table-p data) (setq org-id-counter data))))))) (org-id-counter-load) ;; Load the hash table on Emacs start ;; debug (defun org-id-counter-show () "Display the contents of org-id-counter hash table." (interactive) (message "Contents of org-id-counter hash table:") (maphash (lambda (key value) (message "%s: %s" key value)) org-id-counter)) (defun org-id-counter-reset () "Reset the counter on request. Caution: make sure you make appropriate provisions to not have conflicting IDs" ;(interactive) (setq org-id-counter (make-hash-table :test 'equal))) (provide 'org-id-counter) ``` ![Screenshot_2024-04-29_04-23-26](https://global.discourse-cdn.com/free1/uploads/orgroam/original/2X/6/6482d64f5bc31ff883f2daa04ef5f32908d51091.png) Lightly tested - will update on finding bugs and the like. ---
**Author:** ![alanz](https://yyz2.discourse-cdn.com/free1/user_avatar/org-roam.discourse.group/alanz/32/717_2.png) [@alanz](https://org-roam.discourse.group/u/alanz)\ **Post date:** [April 30, 2024, 6:33pm UTC](https://org-roam.discourse.group/t/custom-org-id-format/3448/2 "2024-04-30T18:33:48Z")
FWIW, I am happy with the normal timestamp format, via ```auto ;; Use an ISO8601 timestamp for IDs (org-id-method 'ts) ``` Which shows up as `20240430T181635.273283` ---
**Author:** ![akashp](https://yyz2.discourse-cdn.com/free1/user_avatar/org-roam.discourse.group/akashp/32/1383_2.png) [@akashp](https://org-roam.discourse.group/u/akashp)\ **Post date:** [April 30, 2024, 7:07pm UTC](https://org-roam.discourse.group/t/custom-org-id-format/3448/3 "2024-04-30T19:07:31Z")
Ofcourse its a very simple yet effective way to ensure uniqueness - although I have trouble reading them at a glance and also keeping manual records of them. ---
**Author:** ![nobiot](https://yyz2.discourse-cdn.com/free1/user_avatar/org-roam.discourse.group/nobiot/32/159_2.png) [@nobiot](https://org-roam.discourse.group/u/nobiot)\ **Post date:** [May 9, 2024, 10:28am UTC](https://org-roam.discourse.group/t/custom-org-id-format/3448/4 "2024-05-09T10:28:35Z")
I use a variation of what @alanz uses. I do not like to use the global variable to keep track of the counter for the day (feels a bit too complex for what we want). The time stamp format is now customizable with Org 9.5 = Emacs 28. I use this format: `"%Y-%m-%dT%H%M%S"`: `=> 2024-05-09T122208`. The part `Thhmmss` makes the ID unique to the second (enough for me) and still readable for me. It’s useful as a time stamp as well. Other variations without global counter may be like these. For what it’s worth… ```auto ;; ISO 8601 format (let ((org-id-method 'ts) (org-id-ts-format "%FT%T")) (org-id-new)) ``` `=> 2024-05-09T12:19:30` ```auto ;; Uniquify without global variable (let ((org-id-method 'ts) (org-id-ts-format "%F:")) (concat (org-id-new) (substring (org-id-uuid) 0 8))) ``` `=> 2024-05-09:a24dd299` You can use a forward slash to divide year, month, and day, of course: ```auto (let ((org-id-method 'ts) (org-id-ts-format "%Y/%m/%d:")) (concat (org-id-new) (substring (org-id-uuid) 0 8))) ``` `=> 2024/05/09:fdb00bd5` ```auto ``` ---
**Author:** ![akashp](https://yyz2.discourse-cdn.com/free1/user_avatar/org-roam.discourse.group/akashp/32/1383_2.png) [@akashp](https://org-roam.discourse.group/u/akashp)\ **Post date:** [May 9, 2024, 3:05pm UTC](https://org-roam.discourse.group/t/custom-org-id-format/3448/5 "2024-05-09T15:05:36Z")
I agree with both you and @alanz in that I think its too overcomplicated for trying to do something simple - I was working in a different context, but I ended by creating this out of whatever was left. I treat this as a more proof of concept - rather than something we should use. – this has some big limitations - insofar as much, syncing between different computers becomes a forgone task without making the thing more complex – I had given up on this and I simply have learnt to live life with the full 'ts format – the absoluteness of time is in itself a global variable. Perhaps this could be an example in context for future readers in how to handle variables :- and save and load them from disk – nothing much more should be used out of it – for it imposes handicaps that are too expensive in nature.