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pages/总复习2023t1.md

@@ -961,6 +961,20 @@
 				- LATER EER
 					- Most useful additional concept of EER model:
 					  specialization/generalization.
+						- Specialization
+							- Process of maximizing differences between
+							  members of an entity by identifying their
+							  distinguishing characteristics.
+						- Generalization
+							- Process of minimizing differences between
+							  entities by identifying their common
+							  characteristics.
+						- Two constraints that may apply to a
+						  specialization/generalization:
+							- participation constraints
+								- May be {{c1 mandatory}} or {{c1 optional}}.
+							- disjoint constraints
+					- Superclass / Subclass
 						- Superclass :-> An entity type that includes one or more distinct
 						  id:: 64895f2f-b868-46ec-9d80-7079eaf3197d
 						  subgroupings of its occurrences.
@@ -974,19 +988,6 @@
 						- Subclass :-> A distinct subgrouping of occurrences of an entity
 						  id:: 64895f39-d886-436b-9afe-ba75d37c8b45
 						  type.
-						- Specialization
-							- Process of maximizing differences between
-							  members of an entity by identifying their
-							  distinguishing characteristics.
-						- Generalization
-							- Process of minimizing differences between
-							  entities by identifying their common
-							  characteristics.
-						- Two constraints that may apply to a
-						  specialization/generalization:
-							- participation constraints
-							- disjoint constraints
-					-
 				- LATER designing ER diagram
 			- DONE Block 3
 			  collapsed:: true