feat(docs): document note ID and collisions

docs/User Guide/!!!meta.json

@@ -3815,14 +3815,6 @@
                                     "mime": "image/jpg",
                                     "position": 10,
                                     "dataFileName": "Text_image.png"
-                                },
-                                {
-                                    "attachmentId": "yGknq3nsWpef",
-                                    "title": "bx-edit-alt.svg",
-                                    "role": "image",
-                                    "mime": "image/svg+xml",
-                                    "position": 10,
-                                    "dataFileName": "Text_bx-edit-alt.svg"
                                 }
                             ],
                             "dirFileName": "Text",
@@ -8109,6 +8101,13 @@
                                     "value": "bx bx-hash",
                                     "isInheritable": false,
                                     "position": 10
+                                },
+                                {
+                                    "type": "relation",
+                                    "name": "internalLink",
+                                    "value": "0vhv7lsOLy82",
+                                    "isInheritable": false,
+                                    "position": 20
                                 }
                             ],
                             "format": "markdown",

docs/User Guide/User Guide/Advanced Usage/Note ID.md

@@ -0,0 +1,16 @@
+# Note ID
+Whereas some applications use file names to uniquely identify notes, Trilium uses the concept of Note ID.
+
+Generally, the Note ID is a 12-character long alphanumeric sequence (including both lower and upper case letter) that is randomly generated for each new note.
+
+## How does the import/export affect the note IDs
+
+When notes are exported, their note ID is kept in the metadata of the export. However when they are imported back in, a new note ID is generated for all the notes. This also includes other entities that are part of the import/export process such as [Attachments](../Basic%20Concepts%20and%20Features/Notes/Attachments.md).
+
+## Note collisions
+
+Since the Note ID is a fixed-width randomly generated number, due to the [pigeonhole principle](https://en.wikipedia.org/wiki/Pigeonhole_principle), there is a possibility that a newly created note will have the same ID as an existing note.
+
+Since the note ID is alphanumeric and the length is 12 we have \\(62^{12}\\) unique IDs. However since we are generating them randomly, we can use a collision calculator such as the one for [Nano ID](https://alex7kom.github.io/nano-nanoid-cc/?alphabet=0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz&size=12&speed=1000&speedUnit=hour) to determine that we'd need to create 1000 notes per hour every hour for 9 centuries in order to have at least 1% probability of a note collision.
+
+As such, Trilium does not take any explicit action against potential note collisions, similar to other software that makes uses of unique hashes such as [Git](https://stackoverflow.com/questions/10434326/hash-collision-in-git). If one would theoretically occur, what would most likely happen is that the existing note will be replaced by the new one.

docs/User Guide/User Guide/Note Types/Text_bx-edit-alt.svg

@@ -1 +0,0 @@
-<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24"><path d="M19.045 7.401c.378-.378.586-.88.586-1.414s-.208-1.036-.586-1.414l-1.586-1.586c-.378-.378-.88-.586-1.414-.586s-1.036.208-1.413.585L4 13.585V18h4.413L19.045 7.401zm-3-3 1.587 1.585-1.59 1.584-1.586-1.585 1.589-1.584zM6 16v-1.585l7.04-7.018 1.586 1.586L7.587 16H6zm-2 4h16v2H4z"/></svg>

src/public/app/doc_notes/en/User Guide/!!!meta.json

@@ -3815,14 +3815,6 @@
                                     "mime": "image/jpg",
                                     "position": 10,
                                     "dataFileName": "Text_image.png"
-                                },
-                                {
-                                    "attachmentId": "yGknq3nsWpef",
-                                    "title": "bx-edit-alt.svg",
-                                    "role": "image",
-                                    "mime": "image/svg+xml",
-                                    "position": 10,
-                                    "dataFileName": "Text_bx-edit-alt.svg"
                                 }
                             ],
                             "dirFileName": "Text",
@@ -8109,6 +8101,13 @@
                                     "value": "bx bx-hash",
                                     "isInheritable": false,
                                     "position": 10
+                                },
+                                {
+                                    "type": "relation",
+                                    "name": "internalLink",
+                                    "value": "0vhv7lsOLy82",
+                                    "isInheritable": false,
+                                    "position": 20
                                 }
                             ],
                             "format": "html",

src/public/app/doc_notes/en/User Guide/User Guide/Advanced Usage/Note ID.html

@@ -12,7 +12,34 @@
     <div class="content">
        <h1 data-trilium-h1>Note ID</h1>
 
-      <div class="ck-content"></div>
+      <div class="ck-content">
+        <p>Whereas some applications use file names to uniquely identify notes, Trilium
+          uses the concept of Note ID.</p>
+        <p>Generally, the Note ID is a 12-character long alphanumeric sequence (including
+          both lower and upper case letter) that is randomly generated for each new
+          note.</p>
+        <h2>How does the import/export affect the note IDs</h2>
+        <p>When notes are exported, their note ID is kept in the metadata of the
+          export. However when they are imported back in, a new note ID is generated
+          for all the notes. This also includes other entities that are part of the
+          import/export process such as&nbsp;<a class="reference-link" href="../Basic%20Concepts%20and%20Features/Notes/Attachments.html">Attachments</a>.</p>
+        <h2>Note collisions</h2>
+        <p>Since the Note ID is a fixed-width randomly generated number, due to the
+          <a
+          href="https://en.wikipedia.org/wiki/Pigeonhole_principle">pigeonhole principle</a>, there is a possibility that a newly created
+            note will have the same ID as an existing note.</p>
+        <p>Since the note ID is alphanumeric and the length is 12 we have&nbsp;
+          <span
+          class="math-tex">\(62^{12}\)</span>&nbsp;unique IDs. However since we are generating them
+            randomly, we can use a collision calculator such as the one for <a href="https://alex7kom.github.io/nano-nanoid-cc/?alphabet=0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz&amp;size=12&amp;speed=1000&amp;speedUnit=hour">Nano ID</a> to
+            determine that we'd need to create 1000 notes per hour every hour for 9
+            centuries in order to have at least 1% probability of a note collision.</p>
+        <p>As such, Trilium does not take any explicit action against potential note
+          collisions, similar to other software that makes uses of unique hashes
+          such as <a href="https://stackoverflow.com/questions/10434326/hash-collision-in-git">Git</a>.
+          If one would theoretically occur, what would most likely happen is that
+          the existing note will be replaced by the new one.</p>
+      </div>
     </div>
   </body>
 

src/public/app/doc_notes/en/User Guide/User Guide/Note Types/Text_bx-edit-alt.svg

@@ -1 +0,0 @@
-<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24"><path d="M19.045 7.401c.378-.378.586-.88.586-1.414s-.208-1.036-.586-1.414l-1.586-1.586c-.378-.378-.88-.586-1.414-.586s-1.036.208-1.413.585L4 13.585V18h4.413L19.045 7.401zm-3-3 1.587 1.585-1.59 1.584-1.586-1.585 1.589-1.584zM6 16v-1.585l7.04-7.018 1.586 1.586L7.587 16H6zm-2 4h16v2H4z"/></svg>