OraclePLSQL-Page1

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👉 What is DATABASE?
A database can be defined as a collection of coherent, meaningful data.

👉 What is DBMS?
DBMS is a system that manages data in a database and allows the inserting, deleting, updating, and processing of data.

Benefits:
1)Stored data can be shared by a single or multiple users.
2)Data integrity can be maintained. Data integrity refers to the problem of ensuring that the database contains only accurate data.
3)Security of data can be implemented.

👉 What is RDBMS?
1)Relational database management system stores data in the form of related tables.
2)An important feature of a relational system is that a single database can be spread among several tables.

👉 Normalization
Through the normalization process, the collection of data in a single table is replaced by the same data being distributed over multiple tables, with a specific relationship being set up between the tables.

👉 Components of SQL

✅Data Definition Language(DDL)
It is a set of SQL commands used to create, modify and delete database structures but not data.
Ex: Create, Alter, Drop

✅Data Manipulation Language(DML)
It is the area of SQL that allows changing data within the database. Ex: Insert, Update, Delete

✅Data Control Language(DCL)
It is the component of the SQL statement that controls access to data and to the database. Ex: Commit, Rollback

✅Data Query Language(DQL)
It is the component of SQL statement that allows getting data from the database and imposing order upon it.

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