What type of ternary relationship CANNOT be depicted as two binary relationships?
A unary relationship
can have one or many maximum cardinalities on either side. A unique attribute is an attribute whose value is different for each entity instance.
How many entities are involved in a binary relationship?
The binary relationship, an association between
two entities
, is by far the most common type in the natural world.
What is depicted by relational schema?
A relational schema is a
visual depiction of the relational database model
. Two columns of a relational table can have the same names. Two columns of a relational table can have the same values.
What is the difference between a unary relationship and a ternary relationship quizlet?
A unary relationship means the degree of the relationship is one, while a ternary relationship means the
degree of the relationship is three
. … A unary relationship means the degree of the relationship is three, while a ternary relationship means the degree of the relationship is one.
Which of the following attributes is defined as having at most a single value for any given entity instance?
By definition,
a simple attribute
is an attribute that cannot be divided in simpler parts that have a different semantic meaning in the real world. A single-value attribute has at most a value for any given entity instance.
Why a ternary relationship is not the same as three binary relationships?
If a ternary relationship is represented instead with 3 binary relationships, there are,
for each endpoint of a relationship
(there are six of them) 4 possibilities (single or multiple, tutal or partial), so in total one can have 24 possible combinations, that this a number of possible specifications which is the …
What is a ternary relationship How is it represented in ERD?
In Ternary relationship
three different Entities takes part in a Relationship
. Relationship Degree = 3. For Example: Consider a Mobile manufacture company. Three different entities involved: Mobile – Manufactured by company.
What is binary relationship in database?
A Binary Relationship is
the relationship between two different Entities
i.e. it is a relationship of role group of one entity with the role group of another entity. There are three types of cardinalities for Binary Relationships − 1. One-to-One.
Which of the following is not a type of database?
Answer:
folder database
is not a type of database.
Which of the following is not a process of generating a good relational schema?
Which of the following is not a process of generating a good relational schema? Explanation:
Joining multiple relations together to form a single relation containing all the attributes
is not a method for the development of good relational schema because it might violate the normal forms if it is combined.
What is a dependent entity?
Data points or entities that may only exist or have certain values if a certain requirement is met by another entity. In a many to many relationship, dependent entities are
created to simplify data models
. For example, many buildings may have many rooms, but each room can only be in one building.
How does intersection data relate to an associative entity?
How does intersection data relate to an associative entity?
An entity that has two or more primary keys derived from the entities that form the intersection of the attributes associated with the original entities
.
Can a ternary relationship have intersection data explain?
Ternary relationships can have intersection data to
describe the combination of one occurrence in each of the three entities
. … Ternary relationships can have intersection data to describe the combination of one occurrence in each of the three entities.
What is the problem associated with having two or more multi valued attributes?
Question: What is the problem with multivalued attributes? Multivalued attributes can cause
problems with the meaning of data in the database
, significantly slow down searching, and place unnecessary restrictions on the amount of data that can be stored.
What are the different types of relationships in DBMS?
- One-to-One Relationship.
- One-to-Many or Many-to-One Relationship.
- Many-to-Many Relationship.
What kind of attribute would be date of birth?
Date of birth would be
a stored attribute
. A one-to-many relationship occurs between two entities in which an instance of one entity can be related to only one instance of a related entity.
Can an entity have 2 relationships?
There can be a number of different relationships between the same two entities
. For example: Employee is assigned to a Project, … One entity can participate in a number of different relationships involving different entities.
What is binary relationship and ternary relationship?
Binary Relationship: a binary relationship is
a relationship of degree two
. That is the relationship contains two participating entities. It can take the form of 1:1, 1:M, or M:N. Ternary Relationship: a ternary relationship is a relationship of degree three.
What is binary relationship and ternary relationship why we need to use ternary relationship?
The binary recursive relationship construct is a diamond with both connections to the same entity. A ternary relationship is an association among three entities. This type of relationship is required
when binary relationships are not sufficient to accurately describe the semantics of the association
.
What is the difference between binary and ternary relationship in database?
A binary relationship is when two entities participate and is the most common relationship degree. A unary relationship is when both participants in the relationship are the same entity. For Example: … A ternary relationship is when
three entities participate
in the relationship.
What are the types of relationship?
There are four basic types of relationships:
family relationships, friendships, acquaintanceships, and romantic relationships
. Other more nuanced types of relationships might include work relationships, teacher/student relationships, and community or group relationships.
What is ternary relationship in DBMS?
In the Ternary relationship, there are three types of entity associates. So, we can say that a Ternary relationship exists
when there are three types of entity and we call them a degree of relationship is
3. Since the number of entities increases due to this, it becomes very complex to turn E-R into a relational table.
What are the different types of constraints on binary relationships?
We can distinguish two main types of binary relationship constraints:
cardinality ratio and participation
. Cardinality Ratios for Binary Relationships. The cardinality ratio for a binary relationship specifies the maximum number of relationship instances that an entity can participate in.
What is binary relationship example?
We can also use binary relations to trace relationships between people or between any other objects. Examples of binary relations between people:
Family relations
(like “brother” or “sister-brother” relations), the relation “is the same age as”, the relation “lives in the same city as”, etc.
How do you read a ternary relationship?
Assume the ternary relationship has participating entities A, B and C (for degree > 3 it gets pretty hairy). The way to read the relationship is
to always isolate 2 out of the 3 participating entities and see how they relate towards the third one
. And you need to do this for all possible pairs.
Which of the following is not a relational database?
2) Non-relational databases, also called NoSQL databases, the most popular being
MongoDB
, DocumentDB, Cassandra, Coachbase, HBase, Redis, and Neo4j. These databases are usually grouped into four categories: Key-value stores, Graph stores, Column stores, and Document stores (see Types of NoSQL databases).
Which of the following is not a feature of a good relational design?
1. Which of the following is not a feature of a good relational design? Explanation:
Allowing redundancy of attributes makes it very difficult for data extraction
. So, It is not a good relational design feature.
Which of the following is not considered as a logical structure of the database?
è Chain
is not a logical database structure to represent the data logically.
Which of the following is not an aggregate function?
Which of the following is not an aggregate function? Explanation:
With is used to create temporary relation
and its not an aggregate function.
Which of the following is not a example of relational database?
Spreadsheet
is not the example of relational database.
Which of the following is not a database software?
The correct answer is
MS word
. MS Word since it’s a word processor. Microsoft Word is a word processor developed by Microsoft.
What is ternary relation in discrete mathematics?
In mathematics, a ternary relation or triadic relation is
a finitary relation in which the number of places in the relation is three
. Ternary relations may also be referred to as 3-adic, 3-ary, 3-dimensional, or 3-place.
Which of these are used to express relationship among relationship?
Explanation:
An ERD
can also be referred as Entity Relationship Model. It is actually a graphical representation which is used for depicting the relationships among the objects, people, concepts, places or any kinds of events within an IT environment.
How ternary associations are mapped to the tables in database?
Each of the
3 entities
and the association between them gets stored in its own database table. … It follows the same concept as the association table of a many-to-many association. It contains the 3 foreign keys of the associated entities and uses all 3 of them as its derived primary key.
What is the difference between an identifying and non identifying relationship?
Identifying relationships exist when the primary key of the parent entity is included in the primary key of the child entity. On the other hand, a non-identifying relationship exists when the primary key
of the parent entity is included in the child entity but not as part of the
child entity’s primary key.
Which is not included in the definition of an entity?
4. Which is NOT included in the definition of an entity? answer:
Action
An entity is a person, place, object, event, or concept. … answer: STUDENT_ID STUDENT_ID depends upon the existence of the STUDENT entity, so it is not a strong entity type.
What is an entity that can serve as the relationship between other entities called?
Entities that exist to represent the relationship between two or more other entities are known as
composite entities
.
Which type of relation requires an associative table?
An associative entity is a term used in relational and entity–relationship theory. A relational database requires the implementation of
a base relation (or base table)
to resolve many-to-many relationships. A base relation representing this kind of entity is called, informally, an associative table.
What is a composite associative entity and when is it used?
Associative (Composite) Entities:
The associative entity is used
to implement a M:N relationship between two or more entities
. This associative entity (also known as a composite or bridge entity) is composed of the primary keys of each of the entities to be connected.
When must a many-to-many relationship be Modelled as an associative entity?
2 Answers. Associative entities are used when you need a relationship to
be involved
in a relationship. For a normal many-to-many relationship between Student and Course , we would use just a diamond. However, if we want to associate Enrollment with Teacher , we can turn Enrollment into an associative entity.
Which type of relationship is not allowed in a relational database?
Relational Database Database | Stored data can be accessed from the relational database because there is a relationship between the tables and their attributes. There is no relationship between data value or tables stored in files. |
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What does does not allow an attribute value to be multivalued?
Only one value at the intersection of a column and row
: A relation does not allow multivalued attributes. Uniqueness: There are no duplicate rows in a relation. A primary key: A primary key is a column or combination of columns with a value that uniquely identifies each row.
Which of the following Cannot be used to modify the data in a database?
Explanation:
The drop keyword is used to delete
the entire relation leaving no trace of it in the memory. Thus it cannot be used to edit the data in the relation.