Notes
,What is Database
The database is a collection of inter-related data which is used to retrieve, insert and
delete the data efficiently. It is also used to organize the data in the form of a table,
schema, views, and reports, etc.
For example: The college Database organizes the data about the admin, staff,
students and faculty etc.
Using the database, you can easily retrieve, insert, and delete the information.
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Database Management System
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o Database management system is a software which is used to manage the
database. For example: MySQL, Oracle, etc are a very popular commercial
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database which is used in different applications.
o DBMS provides an interface to perform various operations like database
creation, storing data in it, updating data, creating a table in the database and a
lot more.
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o It provides protection and security to the database. In the case of multiple users,
it also maintains data consistency.
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DBMS allows users the following tasks:
o Data Definition: It is used for creation, modification, and removal of definition
that defines the organization of data in the database.
o Data Updation: It is used for the insertion, modification, and deletion of the
actual data in the database.
o Data Retrieval: It is used to retrieve the data from the database which can be
used by applications for various purposes.
, o User Administration: It is used for registering and monitoring users, maintain
data integrity, enforcing data security, dealing with concurrency control,
monitoring performance and recovering information corrupted by unexpected
failure.
Characteristics of DBMS
o It uses a digital repository established on a server to store and manage the
information.
o It can provide a clear and logical view of the process that manipulates data.
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o DBMS contains automatic backup and recovery procedures.
o It contains ACID properties which maintain data in a healthy state in case of
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o It can reduce the complex relationship between data.
o It is used to support manipulation and processing of data.
o It is used to provide security of data.
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o It can view the database from different viewpoints according to the
requirements of the user.
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Advantages of DBMS
Controls database redundancy: It can control data redundancy because it
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stores all the data in one single database file and that recorded data is placed in
the database.
o Data sharing: In DBMS, the authorized users of an organization can share the
data among multiple users.
o Easily Maintenance: It can be easily maintainable due to the centralized nature
of the database system.
o Reduce time: It reduces development time and maintenance need.
, o Backup: It provides backup and recovery subsystems which create automatic
backup of data from hardware and software failures and restores the data if
required.
o multiple user interface: It provides different types of user interfaces like
graphical user interfaces, application program interfaces
Disadvantages of DBMS
o Cost of Hardware and Software: It requires a high speed of data processor and
large memory size to run DBMS software.
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o Size: It occupies a large space of disks and large memory to run them
efficiently.
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o Complexity: Database system creates additional complexity and requirements.
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o Higher impact of failure: Failure is highly impacted the database because in
most of the organization, all the data stored in a single database and if the
database is damaged due to electric failure or database corruption then the data
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may be lost forever.
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DATABASE
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What is Data?
Data is a collection of a distinct small unit of information. It can be used in a variety
of forms like text, numbers, media, bytes, etc. it can be stored in pieces of paper or
electronic memory, etc.
Word 'Data' is originated from the word 'datum' that means 'single piece of
information.' It is plural of the word datum.