How different schema layers are related to logical and physical data independence?

The logical schema stays unchanged even though changes are made to file organization or storage structures, storage devices or indexing strategy. Physical data independence deals with hiding the details of the storage structure from user applications.

How external internal and conceptual schema layers are related to the concepts of logical and physical data independence?

How are these different schema layers related to the concepts of logical and physical data independence? External Schema: represents data accessed by end users or application programs, it provides customized information to the end users. … Conceptual schema maps internal schema data to the external schema.

How does the 3 level schema architecture provide data independence?

Data independence occurs because when the schema is changed at some level, the schema at the next higher level remains unchanged; only the mapping between the two levels is changed. Hence, application programs refer-ring to the higher-level schema need not be changed.

What is the difference between logical independence and physical independence?

Physical Data Independence modifies the physical schema without causing the application program to be rewritten. Logical Data Independence modifies the logical schema without causing the application program to be rewritten.

What is the difference between internal & external schema?

Internal Level: Actual PHYSICAL storage structure and access paths. Conceptual or Logical Level: Structure and constraints for the entire database. External or View level: Describes various user views.

What is a concept schema?

A conceptual schema is a high-level description of informational needs underlying the design of a database. It typically includes only the main concepts and the main relationships among them. … This level describes the structure of the whole database for a group of users.

What is the difference between the logical and physical data structure?

The main difference between Logical and Physical Data Model is that Logical data models help to define the data elements and their relationships, while the physical data models help to design the actual database based on the requirements gathered during the logical data modelling.

What is the difference between physical and logical data independence which one do you think is harder to achieve and why?

Logical data independence is more difficult to achieve than physical data independence, since application programs are heavily dependent on the logical structure of the data that they access.

What is the difference between physical and logical design?

The main difference between logical database design and physical database design is that logical database design helps to define the data elements and their relationships, but physical database design helps to design the actual database based on the requirements gathered during the logical data design.

What are the differences between the conceptual logical and physical design of a data warehouse?

The conceptual model is to establish the entities, their attributes, and their relationships. The logical data model defines the structure of the data elements and set the relationships between them. The physical Data Model describes the database-specific implementation of the data model.

What is data independence differentiate between different types of data independence?

The physical data independence is basically used to separate conceptual levels from the internal/physical levels.
…
Difference between Physical and Logical Data Independence :
Physical Data Independence Logical Data Independence
It is easy to retrieve. It is difficult to retrieve because the data is mainly dependent on the logical structure of data.
•
Jun 23, 2021

What is the concept of data independence and explain its importance in database environment?

Data Independence is defined as a property of DBMS that helps you to change the Database schema at one level of a database system without requiring to change the schema at the next higher level. Data independence helps you to keep data separated from all programs that make use of it.

What is the difference between database schema and instance?

The basic structure of how the data will be stored in the database is called schema. Schema is of three types: Logical Schema, Physical Schema and view Schema.
…
Difference between Schema and Instance :
Schema Instance
It is the overall description of the database. It is the collection of information stored in a database at a particular moment.
•
Sep 22, 2021

How view is related to data independence?

Views provide data independence to an application as the application depends on a view but not on a real table. Therefore, any change in the table will not affect the application, and an application will always be independent of the table schema design.

What is data abstraction and data independence explain their types?

Data Abstraction is a process of hiding unwanted or irrelevant details from the end user. It provides a different view and helps in achieving data independence which is used to enhance the security of data. The database systems consist of complicated data structures and relations.

What implies the ability to change the internal schema without changing the conceptual schema?

Physical data independence is the capacity to change the internal schema without having to change the conceptual (or external) schemas. … If the same data as before remains in the database, we should not have to change the conceptual schema.

What is logical schema in database?

A logical data model or logical schema is a data model of a specific problem domain expressed independently of a particular database management product or storage technology (physical data model) but in terms of data structures such as relational tables and columns, object-oriented classes, or XML tags.

What is physical data independence Mcq?

Logical Data Independence: The ability to change the conceptual schema without having to change the view level schema. Physical Data Independence: The ability to change the internal schema without having to change the conceptual schema.