From 2042d24977651e329f154938442968d4effb7860 Mon Sep 17 00:00:00 2001
From: Jet Hughes <jethughes0@gmail.com>
Date: Thu, 22 Sep 2022 10:54:01 +1200
Subject: [PATCH] vault backup: 2022-09-22 10:54:01

---
 content/notes/13-databases-1.md | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/content/notes/13-databases-1.md b/content/notes/13-databases-1.md
index 1e094926e..0541401b7 100644
--- a/content/notes/13-databases-1.md
+++ b/content/notes/13-databases-1.md
@@ -110,3 +110,17 @@ relationship types can have attributes
 	- one to one
 	- one to n
 	- m to n
+- participation
+	- total participation
+		- marked by double line
+		- relationship is required
+	- partial
+		- marked by single line
+		- relationsihp is not required
+
+## weak entities
+- regular tyupes 
+
+![cardinality examples|300](https://i.imgur.com/DmHQaVc.png)
+![participation example|300](https://i.imgur.com/hH0v4bR.png)
+