Multiplicity. Place multiplicity notations near the ends of an association. These symbols indicate the number of instances of one class linked to one instance of the other class. For example, one company will have one or more employees, but each employee works for one company only.
Q. What is a multiplicity of 2?
The number of times a given factor appears in the factored form of the equation of a polynomial is called the multiplicity. The zero associated with this factor, x=2 , has multiplicity 2 because the factor (x−2) occurs twice.
Table of Contents
- Q. What is a multiplicity of 2?
- Q. What is Ooad class diagram?
- Q. How do you show relationships in class diagram?
- Q. Which diagram is used to show interactions between messages are classified as?
- Q. How do you show cardinality in a class diagram?
- Q. How do you read cardinality?
- Q. What is a relationship in ER diagram?
- Q. What are the 3 types of relationships in a database?
- Q. What is a weak relationship in ER diagram?
- Q. What is a relationship called when it is maintained between two entities?
- Q. What is a relationship called when an association is maintained between three entities?
- Q. Which of the following is another name for weak entity?
- Q. Which are the two ways in which entities can participate in a relationship?
- Q. Can you have a many to many relationship?
- Q. Which is the primary key of weak entity?
- Q. Is an association among several entities?
Q. What is Ooad class diagram?
In software engineering, a class diagram in the Unified Modeling Language (UML) is a type of static structure diagram that describes the structure of a system by showing the system’s classes, their attributes, operations (or methods), and the relationships among objects.
Q. How do you show relationships in class diagram?
To show a composition relationship in a UML diagram, use a directional line connecting the two classes, with a filled diamond shape adjacent to the container class and the directional arrow to the contained class.
Q. Which diagram is used to show interactions between messages are classified as?
Discussion Forum
| Que. | The kind of diagrams which are used to show interactions between series of messages are classified as |
|---|---|
| b. | state chart diagrams |
| c. | collaboration diagrams |
| d. | object lifeline diagrams |
| Answer:collaboration diagrams |
Q. How do you show cardinality in a class diagram?
In UML, cardinality is represented by characters: “..1” (meaning that an instance of the first entity class can be associated with no more than one instance of the second class) or “.. *” (meaning that the first entity can be associated with an unlimited number of instances of the second class).
Q. How do you read cardinality?
Cardinality can be 1 or Many and the symbol is placed on the outside ends of the relationship line, closest to the entity, Modality can be 1 or 0 and the symbol is placed on the inside, next to the cardinality symbol. For a cardinality of 1 a straight line is drawn.
Q. What is a relationship in ER diagram?
An entity relationship diagram (ERD) shows the relationships of entity sets stored in a database. By defining the entities, their attributes, and showing the relationships between them, an ER diagram illustrates the logical structure of databases. ER diagrams are used to sketch out the design of a database.
Q. What are the 3 types of relationships in a database?
There are three types of relationships between the data you are likely to encounter at this stage in the design: one-to-one, one-to-many, and many-to-many. To be able to identify these relationships, you need to examine the data and have an understanding of what business rules apply to the data and tables.
Q. What is a weak relationship in ER diagram?
A weak, or non-identifying, relationship exists if the primary key of the related entity does not contain a primary key component of the parent entity. Company database examples include: Customer(CustID, CustName) Order(OrderID, CustID, Date)
Q. What is a relationship called when it is maintained between two entities?
Explanation: Ellipse represents attributes, rectangle represents entity. 6. What is a relationship called when it is maintained between two entities? Explanation: Primary key of one relation used as an attribute in another relation is called foreign key.
Q. What is a relationship called when an association is maintained between three entities?
A relationship degree indicates the number of entities or participants associated with a relationship. A unary relationship exists when an association is maintained within a single entity. A ternary relationship exists when three entities are associated.
Q. Which of the following is another name for weak entity?
Discussion Forum
| Que. | Which of the following is another name for weak entity? |
|---|---|
| b. | Owner |
| c. | Dominant |
| d. | All of the above |
| Answer:Child |
Q. Which are the two ways in which entities can participate in a relationship?
Discussion Forum
| Que. | Which are the two ways in which entities can participate in a relationship? |
|---|---|
| b. | Total and partial |
| c. | Simple and Complex |
| d. | All of the above |
| Answer:Total and partial |
Q. Can you have a many to many relationship?
A many-to-many relationship occurs when multiple records in a table are associated with multiple records in another table. To avoid this problem, you can break the many-to-many relationship into two one-to-many relationships by using a third table, called a join table. …
Q. Which is the primary key of weak entity?
In a relational database, a weak entity is an entity that cannot be uniquely identified by its attributes alone; therefore, it must use a foreign key in conjunction with its attributes to create a primary key. The foreign key is typically a primary key of an entity it is related to.
Q. Is an association among several entities?
Explanation: A relationship is an association among several entities. A relationship specifies how two entities are related. Explanation: A relationship may also have attributes. These attributes are called as descriptive attributes.
