separate user profile from user; names are unique keys

DB_Structure.md

@@ -3,17 +3,22 @@
 This is the structure of the database.
 This structure only contains the basic elements needed for the main functions of the app.
 It is expected to evolve in the development of the app.
-- USER: a user of the app
-- EVENT: an event created in the app, created by a user
+- USER: a user of the app, metadata reference the attributes defined by https://supabase.com/docs/guides/auth/auth-user-management
+- USER_PROFILE: information related to a user
+- EVENT: an event created in the app, created by a user; the user has the choice to create the event for an association (host relation) or for himself
 - TAG: a tag that can be linked to the user's preferences and the event's tags list
 - ASSOCIATION: an association that has some committee members and followers, the committee members can create events for the association
+
 ## Diagram
 ```mermaid
 erDiagram
+    USER_PROFILE {
+        string userId PK,FK
+        string name UK
+    }
     USER {
         string userId PK
-        string name
-        location location
+        string metadata
     }
     EVENT {
         string eventId PK
@@ -26,21 +31,23 @@ erDiagram
     }
     TAG {
         string tagId PK
-        string name
+        string name UK
     }
 
 ASSOCIATION {
     string associationId PK
-    string name
+    string name UK
     string description
 
 }
     USER }o--|| EVENT : organizer
     USER }o--o{ EVENT: participant
     USER }o--o{ TAG: interested
+    USER ||--|| USER_PROFILE: profile
     EVENT }o--o{ TAG: tags
     TAG }o--o{ TAG: subtag
     ASSOCIATION }|--o{ USER: committee_member
     ASSOCIATION }o--o{ USER: follower
+    ASSOCIATION }o--o{ EVENT: host
 ```
 For mermaid syntax, see: https://mermaid.js.org/syntax/entityRelationshipDiagram.html