0
How do you create a table using the entities and attributes you want to use and listing at least three entities and at least four attributes for each entity?
Entity is an object, can be independent or dependent object. e.g A Student, Lecturer OR Employee can be a entity where as the attributes are the properties of the entity. e,g name, age, birthdate, degree.
to answer your question create 3 X 4 matrix, add entity names in column heading and attributes in a row label. and fill in the information for each entity.
What else can I help you with?
How is subtraction like adding?
Subtraction is nothing like addition. If you are talking about addition, it means that 1+1=2 - one entity + one entity = two entities. Entities=numbers. However, for subtraction it is the opposite. 1-1 = 0 - one entity eats/- one entity = zero entities. There are no other entities to eat except for itself. Thus when it eats itself, there are no more entities left.
Why does 1 plus 1 equal 2?
We assign the symbol "1", pronounced by the word sound "wun", to a single entity, for purpose of letting all know that whatever that entity is, it is a single entity. If then another entity appears, by any means, and we wish to describe that there is now an additional single entity, we assign the symbol "2", pronounced by the word sound "too". Note that the entities may each be the same, as in "2" apples. Or the entities may be different, say an apple and orange, but we simply wish to describe how many entities of any type are there. Whenever we place a single entity next to another single entity, we call the combined entities "2", and know that there are thus that many entities there, regardless as to any other characteristics they may have. We then decided that if we had "2" entities, and added another single entity, still called "1", that we'd call the end result three. And so on. Thus 1 plus 1 equals 2 because "1" stands for a single entity, and when we add it to another single entity, we've agreed to label that "2".
Could two schemas have some data items in common?
Yes, two schemas can have some data items in common. This typically occurs when they share similar entities or attributes, allowing for overlap in the data they represent. For example, both schemas may include a "Customer" entity with attributes like "CustomerID" and "Name." However, the overall structure and other data items in the schemas may differ based on their specific purposes.
Points of difference between attribute and entity?
attribute is a charactarestic of an entity.For example,student entity is there in which we may have student id,course,phoneno,addrs....stuedent id,course,phone no.,addrs are attributes as an individuals but they represent the charactarestics of student entiy
What is definition of the four fundamentals operation in math?
Addition: Summing two or more entities Subtraction: Taking away one entity from another entity Multiplication: Summing an entity to itself a given number of times (successive addition) Division: Taking away from a first entity a second entity (could be the same as the first entity) repeatedly until this process is not possible anymore (successive subtraction). The number of times such operation can be made may be a whole number of times, or a whole number of times (including zero times) and a left over part that is smaller than the second entity
What are the entities and attributes.give one example?
Entities are one type of storage place where we can store information whereas attributes is the piece of information for that entity. Example : The book is the entity set. Title, price, author name all are the attributes of the book entity.
Difference between specialization and generalization?
As the name implies, Generalization is going general. For example if you have entities like Medical-student, Engineering - student, Architecture - student so on, you can generalize and create an entity called Student (higher level entity) so others will be sub entities (lower level entities) of Student entity. One thing to keep in mind is that, the generalized entity is the union of all the sub entities, in the sense it will contain everything that is in its sub entities. This is Bottom Up approach! Specialization is about going specifically. For a given entity you create sub entities. For example if Staff entity is there, you create Maintenance staff, IT staff, Executive staff so on. Here the higher level entity (Employee) is given and we create the lower level entities. However unlike in Generalized entity, the higher level entity is NOT union of its lower level entities. Sub entities here will use some things from its higher level entity plus things on its own. This means that there could be things that's in lower level entities but not in higher level entity.
What is E-R model. What is an Entity set?
The E-R model is a data model used to describe the relationships between entities in a database. An Entity set is a collection of similar entities (objects) with shared attributes that are grouped together in the database.
What is difference between object and entity?
A database object is represented as one of the following: database, schema, table, column, primary key, and foreign key A database Entity is: An entity is a thing or object of importance about which data must be captured. All things aren't entities - only those about which information should be captured. Information about an entity is captured in the form of attributes and/or relationships. If something is a candidate for being an entity and it has no attributes or relationships, it isn't an entity. Database entities appear in a data model as a box with a title. The title is the name of the entity.
What is week entity sets?
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.Wikipedia
Difference between entity type and entity set?
lets understand them all: 1.An Entity is a real world "thing" which have independent existence. 2.Entity type is a category. 3.entity type is strictly calling, "an instance of entity type". 4.An entity type defines a collection of entities that have the same attributes. 5.Entity set : the collection of all entities of a particular entity type in the database at any point of time is called Entity set.
What is the relationship between entities and attributes?
Entities and attributes unable you to explicitly define what information, or data, is beingstored in the database. Relationships are the other powerful feature of relational modelingand give the modeling technique its name. A relationship is a logical linkage between twoentities that describes how those entities are associated with each other. Think ofrelationships as the logical links in a database that turn simple data into useful information.For instance, our definition of a teacher reads: “A person employed by the college who isresponsible for instructing students in a class.”
Possessive form of the word entity?
Possessive: entity's Plural: entities Possessive plural: entities'
Why associative entity use in ER model?
Associative entities are used in Entity-Relationship (ER) models to represent relationships between two or more entities. They help to model complex relationships that have attributes of their own. By using associative entities, we can accurately capture the associations between the main entities and represent them in a clear and normalized way.
Entity type vs entity instance?
Entity Type : A collection of entities that share common properties or characteristics. for example student is an entity type with common attributes such as student_ID , Name, Class etc. These characteristics are common to all students. Entity Instance: A single occurrence of a particular entity type is called entity instance..
What should be the erd for website design?
ERD is an Entity Relationship Diagram which is a graphical representation of database entities (tables, table columns, table definitions, attributes) and inter-relationships between these entities (how the tables are connected).
How to draw entity relationship diagram?
To draw a relationship diagram, start by placing relationship at the center of the paper. Connect entities to the relationship, and branch out with the different attributes.
