RDBMS (Relational Database Management System) is one of the types of DBMS which shows Relational between the Tables (where data are stored in the form of ROWS & COLUMNS).
In
other words, Relational database is a type of
database that allows us to identify and access data in relation to another
piece of data in the database. It stores data in rows and columns in a series
of tables to make processing and querying efficient.
Rows (Tuples) are Horizontal while Columns (Headers are called Attributes – ID, Name, etc.) are Vertical in a Table.
Degree
of Relation = No. of Columns
Cardinality
= No. of Rows
Data present inside the Column is called ‘Domain Values’.
Objectives
for creating the Tables:
a) Every table must have
a Unique Name.
b) Every Cell must have a
Single Value.
c) Each Column must have
a Distinct Name.
d) No Duplicates in a
Row.
Different
types of RDBMS and their usage in some Companies:
1) MySQL (e.g.: Bank of England)
2) Oracle (e.g.: Bank of America)
3) NETEZA
4) SQL Server Management
5) MS SQL (e.g.: Cognizant)
6) Informix (e.g.: Walmart)
7) Postgre SQL (e.g.: MBRDI Mercedes Benz)
Application
of RDBMS:
a) Business
b) Airlines
c) Retail
d) Education
Language
used to process (update / insert / delete) the data in RDBMS is called ‘Structured / Standard Query Language
(SQL)”.
SQL
uses in RDBMS:
a) Execute the queries.
b) Retrieve the data
c) Insert the data
d) Update the data
e) Delete the data
f) Create new database
g) Create new tables
h) Create new stored
procedures
i)
Create
views in SQL
Different types of SQL
statements:
A) DDL
(Data Definition Language)
are instructions like CREATE, DROP, ALTER & TRUNCATE.
B) DML
(Data Manipulation Language)
which are INSERT, UPDATE & DELETE.
C) DQL
(Data Query Language)
à SELECT.
D) TCL
(Transaction Control Language) à COMMIT, ROLLBACK
& SAVEPOINT.
E) DCL (Data Control Language) use by Admins which are GRANT & REVOKE.
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