diff --git a/DB - Schema.-.md b/DB - Schema.-.md
index 308ff3a..0f2e35c 100644
--- a/DB - Schema.-.md	
+++ b/DB - Schema.-.md	
@@ -1,5 +1,7 @@
 This chapter contains the structure of our internal database tables.
 
+* := unique
+
 ### User
 
 - Name