Basic of database and sql command

1. Basic of database and
SQL commands
Made By:
Krutika Malvi :- 224510307064
Niyati Mandaliya :- 224510307066

2. BASIC OF DATABASE
 WHAT IS DATABASE?
 A database is a collection of inter-related data.
 Data is stored in organized manner so that it is available to many users for different purpose.

3.  WHAT IS THE PURPOSE OF DATABASE?
 To store data.
 To provide an organizational structure for data.
 To provide a mechanism for querying, creating, modifiying and deleting data.
 It provides data security.
 DATABASE MANAGEMENT SYSTEM:-
 A database management system is a collection of inter-related data and a set of programs to
manipulate those data.
 Data manipulation involves various operation such as storing, modifying, removing and
retrieving data.
 In other words, DBMS can be described as –
DBMS = Database + A set of programs

4.  Where a Database is referred to as DB and a set of programs is referred to as MS
(Management System).
 A database management system is also referred to as a database system only.
 APPLICATIONS:-
 Banking system
 Inventory system
 Library system
 Railway reservation system
 College/University
 Hospital management system
 Cyber-cafe management system

5.  DATA-ITEMS (FIELDS):-
 A data-item is a character or group of characters (alphabetic or numeric) with a
specific meaning.
 It is also called a data-item.
 It is represented in the database by a value.
 For example, customer id, name, city all are fields for the customer.
 RECORD:-
 A record is a collection of a logically related fields.
 Each field in a record contains a fixed size and data type.
 For example, a collection of fields – id, name, city – forms a record for the customer.
 A record consists of values for each fields.

6. Database
 FILES:-
 A file is a collection of related records.
 These records are generally arranged in a specific sequence.
File File
File
Record Record Record
Field Field Field

7. Introduction to SQL:
 What is SQL?
 SQL is a Structured Query Language, is a domain-specific language designed for
managing and query relational databases.
 It is relatively easy to learn
 Basic command set has vocabulary of less than 100 words
 Nonprocedural language
 American National Standards Institute (ANSI) prescribes a standard SQL
 Several SQL dialects exist

8.  SQL commands can be categories into five main types:
 1.DATA DEFINITION LANGUAGE:
-Create database objects, such as tables, indexes and
views ,alter, truncate and drop.
-Define access rights to those database objects.
 2.Data Manipulation Language:
-Includes commands to insert , update, delete.
 3.Data Control Language:
-Used to control the data stored in database.
-includes grant and revoke.
 4.Transection Control Language:
-Performs the task of a transection.
-Include commit, save point and rollback.
 5.Data Query Language:
-In order to see the present data.
-Includes select.

9. Data Definition Language:
 CREATE:- To create the table
 Syntax:
 CREATE TABLE table_name
(column name 1 datatype
(size), column name 2 datatype
(size), column name n datatype
(size));
 Example:
 CREATE TABLE std_info (std_id
number (10) primary key,
std_name varchar(15),
std_branch varchar (10));
 Output: Table Created.

10.  ALTER: To alter table in SQL
 Syntax:
 ALTERTABLE table_name ADD column_name
datatype (size);
 Example:
 ALTER TABLE std_info ADD sem number(3);
Output: Table Altered.

11.  TRUNCTE: To remove all the rows from the
table.
 Syntax:
 TRUNCATE TABLE table_name;
 Example:
 TRUNCATE TABLE std_info;
 Output: Table Truncated.

12.  DROP: To remove on existing table.
 Syntax:
 DROP TABLE table_name;
 Example:
 DROP TABLE std_info;
 Output: Table Dropped.

13. Data Manipulation Language:
 INSERT: To insert rows into an
existing table / data in a table.
 Syntax:
 INSERT INTO table_name
(columnName N) values (value 1,
value2, value N);
 Example:
 INSERT into std_class values
(001,’Niyati’);
 Output: 1 Row Inserted.

14.  UPDATE: To modify the data in existing table.
 Syntax:
 UPDATE table_name SET column_name= value
where condition;
 Example:
 UPDATE std_class SET std_name=‘Krutika’
where std_no=001;
 Output: 1 Row Updated.

15.  DELETE: To remove single or a multiple
records from the existing table that is known
as delete.
 Syntax:
 DELETE from table_name where condition;
 Example:
 DELETE from std_class where std_no=001;
 Output: 1 Row Deleted

16. Data Control Language:
 It is use to control access to data which
are stored in database.
 GRANT:
 Syntax:
 GRANT privilege_list ON object_name
TO user_name [with GRANT option];
 Example:
 GRANT ALL ON std_info TO XYZ WITH
GRANT OPTION;
 Output: Grant succeeded

17.  REVOKE: Cancel previously granted or a
denied permission.
 Syntax:
 REVOKE privilege_list ON object_name FROM
user_name;
 Example:
 REVOKE ALL ON SYSTEM std_info from xyz;
 Output: Revoke Succeded.

18. Transection Control Language:
 COMMIT: Commiting a transection. It can be
commit by either explicity or implicity.
 1.Explicit Commit: It makes all change
permanent made during the transaction.
 Syntax and Example:
 Commit;
 Output: Commit Completed.
 2.Implicit Commit: Some
operation which forces a
commit to occure
automatically even user don’t
specify to commit command.

19.  ROLLBACK: Cancelling a transection.
 Syntax & Example:
 Rollback;
 SAVEPOINT: Cancelling a transection
partially. Used to terminate the current
transection portal.
 Syntax:
 ROLLBACK TO SAVEPOINT
Savepoint_name;
 Syntax:
 Savepoint Savepoint_name;
 Output: Rollback Completed.
 Output: Save point Created.

20. Data Query Language:
 SELECT:
 Syntax:
 SELECT* from table_name;
 Example:
 SELECT* from std_class;
 Output:
S_Name S_Roll no
A 01
B 02