Question

1. What is a DBMS, and what are its functions (roles)? What are its advantages, and what are its disadvantages (potential cost of implementing a database system)?
2. Explain why database design is important.
3. List and describe the different types of databases.
4. What are the main components of a database system?
5. What are metadata?

Answer 1

1) DBMS: Database is a collection of data,management systems is a set of programs to store and retrieve those data that is present in the database.So DBMS is a collection of data and set of programs to store and retrieve those data in easy and efficient manner.

Example of DBMS software:MySQL,Oracle,etc..

Functions of DBMS:

Data Dictionary Management,

Data Storage Management,

Data Transformation and presentation,

Security Management,

Multiple Access Control,

Backup and Recovery Management,

Data Integrity Management,

Database access languages,

Databases Communication Interfaces.

Advantages of DBMS:

Data Abstraction,

Controlling Data Redundancy,

Minimized data inconsistency,

Data Manipulation Easily,

Data can be shared,

Data security,

Support multiusers views,

Concurrent access.

Disadvantages of DBMS:

Cost of hardware and software,

Cost of data conversion,

Cost of staff training.

Reason database design is important:

There is some data we need to store it could be informations about customer employers or employees,etc.. and these data can be in any format like text,amount,dates,numbers,images,documents,audio,video,etc.. so we can store these data in text files or spreasheets and use folders to organize files,but the reason database design is important is when small businesses use these text files or spreadsheets this might work for years, but,problems like size of data ,ease of updating data,accuracy,security,redundancy,incomplete data and integrity of data but in database multiple people can modify data at the same time,validation takes place,security is implemented,recovery is available.

Different types of databases:

Centralized database:One database+multiple users.

Distributed database:Multiple database+multiple users.

Personal database:Single database+single user.

End User database:Used for different applications.

Commercial database:User have to pay for accessing data,

Relational database:Data ->tables->i)Rows->tuples/record,ii)Columns->attribute.

Cloud database:Data is stored in cloud built for virtual environment,

Object oriented database:Object oriented programming+Relational database(objects and data),

Graph database:i)nodes->entity,ii)edges->relationship between entities.

Main comnponents of database system:

Users:Application programmers,end users,db administrators.

Software:Control the organization,storage,management,retrieval of data in database.

Hardware:Pc to a network of components,storage devices like hard disk,and i/o devices like monitor,printer,etc..

Data:numerical data,non numerical data,logical data.

Metadata:

Data about data.The database system stores data about this database.Example : schema, when database created databae stores schema.

Answer 2

https://cselearnmore.com/what-is-a-dbms-explain-the-functions-of-dbms/