Participation Constraints And Existence Dependencies | participation constraints in dbms

#participationconstraints #dbms #erdiagram
Participation constraints and existence dependencies
What are we going to learn?participation constraints in dbms,total and partial participation in dbms,participation in dbms,participation in er diagram
What are existence dependencies?
Total participation constraints
Partial participation constraints
Minimum cardinality constraint
Maximum cardinality constraint

Example
What are participation constraints?
The participation constraint specifies whether the existence of an entity depends on its being related to another entity via the relationship type.
This type of constraint specifies the minimum number of relationships an entity can participate in, and is also called minimum participation constraints.
Two types of participation constraints:
Participation constraints are of two types:
Total participation constraint
Partial participation constraint

Total participation:
Total participation means that every entity in a set must be related to the other entity set via that one relationship.
Since all the entities are related to the other entity via that relationship, its called “Total participation cardinality”.
Total participation is also known as existence dependence.
Example
Partial participation constraints
Partial participation constraints mean that some of the entities from one entity set are related to another entity set, via that one relationship but not necessarily all the entities are related.
Example
Minimum cardinality constraint
Minimum cardinality constraint specifies the minimum number of relationship instances that each entity can participate in.
Example
Maximum cardinality constraint
Maximum cardinality constraint specifies the maximum number of relationship instances that each entity can participate in.
Example
Representation