This document discusses the different languages used to interact with databases: 1. DDL (Data Definition Language) is used to define the database schema and includes commands like CREATE, DROP, ALTER, and RENAME. 2. DML (Data Manipulation Language) manipulates the data and includes INSERT, UPDATE, and DELETE commands. 3. DCL (Data Control Language) deals with user privileges and permissions using GRANT and REVOKE commands. 4. DQL (Data Query Language) retrieves data using the SELECT command. 5. TCL (Transaction Control Language) controls transactions with COMMIT, ROLLBACK, and SAVEPOINT commands.

1. FIRSTUP
CONSULTANTS
DATABASE
LANGUAGE AND
STRUCTURE
Week 7
Data science
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2. FIRSTUP
CONSULTANTS
DDL ( DATADEFINITION LANGUAGE)
1) Create
2) Drop
3) Truncate
4) Alter
5) Rename
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3. FIRSTUP
CONSULTANTS
CONTINUE…
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• Syntax:
< create table table name <field 1> < data type>
• Rename < rename table name to new name>
Rename emp to emp2
Select * from emp 2:
• Alter < alter table = table name add column name , data type.
< alter table emp2 add eadd varchar (30)
• Truncate = truncate = table name
Table record delete not delete table
< truncate table emp2>
< desc emp2>
• Drop = drop table , table name
• Permanent delete
• < create table of student >
• < drop table student>
• <desc student>

4. FIRSTUP
CONSULTANTS
DML ( DATA MANIPULATION LANGUAGE)
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• Insert
• Update
• Delete
• Syntax:
• < insert into < table name > values
• < create table>
• < insert into singer values ( asim azhar , Lahore):
• < update < table> set < field> = < update> where < field> = < reference data>
• < update singer set name = atif aslam , Lahore
• < delete from <table name>
• <delete from singer>
• <Delete from singer where asim azhar 1> condition statement

5. FIRSTUP
CONSULTANTS
DCL ( DATACONTROL LANGUAGE)
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• Privilege is a permission given by database.
• SQL , DCL command deals with privileges.
• Grant: It helps to provide any kind of access to any user.
• Revoke: It is used to take back the access from users.
• syntax: < create database user name system >
• < select table>
• < create user arif identified by pwd;>
• < connect to user arif and password>
• < grant connect to arif > we give the privilege and give grant
• < connect >
• <revoke delete on select table>
• < revoke all on select table>

6. FIRSTUP
CONSULTANTS
DQL (DATAQUERY LANGUAGE)
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• It is used to retrieve information from database.
• It has only one select command.
• Syntax :
• Select * from < table name>
• < create table>
• < select * from stu;>
• < select * from stu where roll=2>

7. FIRSTUP
CONSULTANTS
TCL (TRANSACTION CONTROL LANGUAGE)
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• It control the transaction of database it has three commands.
• Commit
• Rollback
• Save point
Syntax:
• Commit command: the use of commit command to store permanent record in server.
• Create table < commit < commit complete>
• Rollback : one step back if you use rollback query after commit doesn’t not give output
• < insert into player values(3, ‘ rohit’, 264);
• < rollback they take it back and have 2 rows.
• Save point < save point we have 5 records>
• < rollback + save point > we see 10 records
• < save point A :>
• < insert 5 records>
• < save point B>
• < we have 10 records>