DATABASE

A database is a collection of inter-related data which helps in the efficient retrieval, insertion, and deletion of data from the database and organizes the data in the form of tables, views, schemas, reports, etc.
For Example, a university database organizes the data about students, faculty, admin staff, etc. which helps in the efficient retrieval, insertion, and deletion of data from it.

DATABASE MANAGEMENT SYSTEM

Database management system is a software which is used to manage the database.
For example: MySQL, Oracle, etc are a very popular commercial database which is used in different applications.
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.
It provides protection and security to the database. In the case of multiple users, it also maintains data consistency.

DDL

DDL is the short name for Data Definition Language, which deals with database schemas and descriptions, of how the data should reside in the database.





• CREATE: to create a database and its objects like (table, index, views, store procedure, function, and triggers).


• ALTER: alters the structure of the existing database.


• DROP: delete objects from the database.


• TRUNCATE: remove all records from a table, including all spaces allocated for the records are removed.


• COMMENT: add comments to the data dictionary.


• RENAME: rename an object.

DML

DML is the short name for Data Manipulation Language which deals with data manipulation and includes most common SQL statements such SELECT, INSERT, UPDATE, DELETE, etc., and it is used to store, modify, retrieve, delete and update data in a database.





• SELECT: retrieve data from a database.


• INSERT: insert data into a table.


• UPDATE: updates existing data within a table.


• DELETE: Delete all records from a database table.


• MERGE: UPSERT operation (insert or update).


• CALL: call a PL/SQL or Java subprogram.


• EXPLAIN PLAN: interpretation of the data access path.


• LOCK TABLE: concurrency Control.

DCL

DCL is short for Data Control Language which acts as an access specifier to the database,basically to grant and revoke permissions to users in the database.





• GRANT: grant permissions to the user for running DML(SELECT, INSERT, DELETE) commands on the table.


• REVOKE: revoke permissions to the user for running DML(SELECT, INSERT, DELETE) command on the specified table.

TABLE
ATTRIBUTES
TUPLES	ROLL-NO	NAME	CLASS	AGE	GENDER	GPA
	1	Arun	Cse	18	Male	9.3
	2	Preethi	Aiml	17	Female	9.5
	3	Anjali	Ds	19	Female	9.7
	4	Kiran	Mech	18	Male	9.2
	5	Lavanya	Ece	17	Female	9.4
	6	Vikram	Civil	18	Male	9.6

DBMS allows users the following tasks:

• Data Definition:It is used for creation, modification, and removal of definition that define the organization of the data in the database.


• Data Updation: It is used for the insertion, modification, and deletion of the actual data in the database.


• Data Retrieval: It is used to retrieve the data from the database which can be used by applications for various purposes.


• 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.

Advantages of DBMS

• Controls database redundancy: It can control data redundancy because it stores all the data in one single database file and that recorded data is placed in the database.


• Data sharing: In DBMS, the authorized users of an organization can share the data among multiple users.


• Easily Maintenance: It can be easily maintainable due to the centralized nature of the database system.


• Reduce time: It reduces development time and maintenance need.


• Backup: It provides backup and recovery subsystems which create automatic backup of data from hardware and software failures and restores the data if required.


• multiple user interface: It provides different types of user interfaces like graphical user interfaces, application program interfaces.

Disadvantages of DBMS

• Cost of Hardware and Software: It requires a high speed of data processor and large memory size to run DBMS software.


• Size: It occupies a large space of disks and large memory to run them efficiently.


• Complexity: Database system creates additional complexity and requirements.


• 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 may be lost forever.

Thank You