0
Want this question answered?
Be notified when an answer is posted
Add your answer:
Earn +20 pts
What does the cardinality ratio specify?
The cardinality ratio specifies the number of relationship instances that an entity can participate in.
Is association class always many-to-many?
In general, an association class is many-to-many if there are no numerical (cardinality) attributes on the association. If you want the association class to represent a many-to-one relationship, then the cardinality on the "one" side of the relationship should be marked with 1.However, some developer conventions will not mark an association with cardinality when the cardinality is unknown. In these environments an unmarked association does not tell you anything about whether you have a many-to-many or many-to-one relationship. To indicate the many side of the relationship you should mark it with a cardinality implying "many", i.e. *, [0..n], [1..n], etc.To answer the specific question: An association class is not always many-to-many.
What is the difference between Cardinality and Degree?
Degree the number of entity types that participate in a relationship.
What is cardinality ratio in ER diagram?
It specify the number of relationship instances that an entity can participate in.
What is the difference between cardinality and degree of relationship in relations in database management?
bal amar
What is cardinality in an ER diagram?
An E-R diagram may also indicate the cardinality of a relationship. Cardinality is the number of instances of one entity that can, or must, be associated with each instance of another entity. In general we may speak of one-to-one, one-to-many, or many-to-many relationships. There are several different styles used to draw Entity-Relationship diagrams. The Kendall and Kendall text uses the Crow's Foot notation. Using this notation entities are represented by rectanges and relationships are indicated by lines connecting the rectangles. Cardinality is shown by a series of "tick marks" and "crows feet" superimposed on the relationship lines.
What is the cardinality of the interval from zero to one including zero but not including one?
The cardinality of [0,1) is equal to the cardinality of (0,1) which has the same cardinality as the real numbers.
What is cardinality in dbms?
Cardinality is the number of attributes in the table.
What is the cardinality of a data type eg integer?
Cardinality is the total number of unique occurances of an entity (e.g. person, organization, or transaction) that can be included in a relationship. A URI/URL, e-mail, phone number should be unique, providing a high cardinality. This means that each of the entity values would be represented at least once in a relationship. A lower cardinality value would be something like a bit, or boolean value. This value will only occur twice before becoming redundant in a relationship. So a data type value of an integer could be either low or high, depending on what the data is used for. If the values are only 0-6, then there are only 6 occurances of the data, if the field is open to the full range of data then it would be of extremely high cardinality.
What is cardinality ratio in DBMS?
The ration Between total Participation and partial participation is called as Cardinality ration.
Explain what cardinality constraints are and how they impact on database design?
Cardinality constraints are rules that define the relationships between tables in a database. They determine how many instances of one entity can be associated with another entity. For example, a cardinality constraint of "one-to-one" means that each instance of one entity can be associated with only one instance of another entity. Cardinality constraints impact database design by helping ensure data integrity and preventing inconsistencies or anomalies. They guide the creation of tables, their relationships, and the use of foreign keys for maintaining data relationships.
What is cardinality of 15?
The cardinality of 15 is equal to the number of elements in the set. Since 15 is only one number, its cardinality is 1.
