update er diagram

README.md

@@ -92,3 +92,47 @@
     pip install -e .[dev,alembic]
     alembic -n cloud revision --autogenerate -m "new feature"
     alembic -n cloud upgrade head
+    ```
+#### Entity Relationship Diagram
+
+```mermaid
+---
+title: ERD
+---
+erDiagram
+    a[PERSON] {
+        integer id PK
+        string firstname
+        string lastname
+        JSONB others
+        Enum(Role) role "developer, maintainer, viewer"
+        list[SKILL] skills "PERSON_SKILL_LINK.skill_id"
+        list[PERSON] parent_friendships "FRIENDSHIP.parent_person_id"
+        list[PERSON] child_friendships "FRIENDSHIP.child_person_id"
+    }
+    b[FRIENDSHIP] {
+        integer parent_person_id(ppid) PK,FK "PERSON.id"
+        integer child_person_id(cpid) PK,FK "PERSON.id"
+    }
+    c[SKILL] {
+        integer id PK
+        string name
+        list[PERSON] persons "PERSON_SKILL_LINK.person_id"
+    }
+    d[PERSON_SKILL_LINK] {
+        integer person_id PK,FK "PERSON.id"
+        integer skill_id PK,FK "SKILL.id"
+
+    }
+    e[ARTICLE] {
+        integer id PK
+        string title
+        string description
+        vector(20) factors
+        ts_vector ts_vector "English title + description"
+    }
+    a||--o{b : ""
+    a||--o{d : ""
+    d}o--||c : ""
+
+```