2. DATABASE
• Organized collection of data
• DBMS – Data Base Management System
• Ex. Oracle, Microsoft SQL Server, IBM DB2
• 2 types of DBMS
– Flat-file database
– Relational database
3. SQL
• Structured Query Language -> RDBMS
• A little History
– Developed by Donald D. Chamberlin & Raymond F.
Boyce at IBM in 1970
– Initially it was named as SEQUEL (Structured
English Query Language)
• Queries – most commonly used operation & can be
done by SELECT
• SQL is not case sensitive.
4. SQL for…
• Execute queries against database
• Retrieve data from database
• Insert, Update, Delete records in database
• Create new tables in database
• Set permissions on tables
• “Persons” table in database
ID Firstname Lastname Address City
1Pratik Rathod memnagar Ahmedabad
2Pranav Agarwal Paldi Ahmedabad
3Karan Koria Girnar Junagadh
5. SQL Statements
• Not case sensitive
• Semi columns
• SQL - DML – Data manipulation language SQL
- DDL - Data definition language
DML DDL
CREATE
SELECT DATABASE
UPDATE ALTER DATABASE
DELETE CREATE TABLE
INSERT INTO ALTER TABLE
DROP TBALE
CREATE INDEX
DROP INDEX
6. SQL Syntax & Statements
• SELECT
Syntax : SELECT column_name(s) FROM table_name
Examples:
1) SELECT LastName,FirstName FROM Persons
2) SELECT * FROM Persons (* is a quick way to select all the columns)
Where our selected columns stored????...
ID Firstname Lastname Address City
1Pratik Rathod memnagar Ahmedabad
2Pranav Agarwal Paldi Ahmedabad
3Karan Koria Girnar Junagadh
7. SQL Syntax & Statements
• SELECT DISTINCT • Where (clause)
Syntax : Syntax :
SELECT DISTINCT column_name(s) SELECT column_name(s) FROM table_name
FROM table_name WHERE column_name operator value
Example: Example:
SELECT DISTINCT City FROM Persons SELECT * FROM Persons WHERE
City=‘Ahmedabad‘
City
Ahmedabad
ID Firstname Lastname Address City
Junagadh 1Pratik Rathod memnagar Ahmedabad
2Pranav Agarwal Paldi Ahmedabad
8. SQL Syntax & Statements
• Operators in WHERE • CREATE TABLE
= Equals Syntax :
<> or != Not equal CREATE TABLE table_name
> Greater than (
< Less than column_name1 data_type,
column_name2 data_type,
>= Greater than or equal column_name3 data_type,
<= Less than or equal ....
)
Example:
CREATE TABLE Persons
(
Id int,
LastName varchar(255),
FirstName varchar(255),
Address varchar(255),
City varchar(255)
)
9. SQL Syntax & Statements
• AND (Operator) • AND & OR together
Ex. Ex.
SELECT * FROM Persons SELECT * FROM Persons WHERE
WHERE FirstName=‘Pranav‘ AND LastName=‘Agarwal'
LastName=‘Agarwal‘ AND (FirstName=‘Pranav' OR
FirstName=‘Pratik')
• OR (Operator)
Ex.
SELECT * FROM Persons
WHERE FirstName=‘Pranav'
OR FirstName=‘Pratik'
10. SQL Syntax & Statements
• ORDER BY (Clause) • INSERT INTO
Syntax : SELECT column_name(s)
FROM table_name
– To insert a new row
ORDER BY column_name(s) ASC|DESC Syntax : INSERT INTO table_name
(column1, column2, column3,...)
Ex. VALUES (value1, value2, value3,...)
1) SELECT * FROM Persons Ex.
ORDER BY LastName
1) INSERT INTO Persons
2) SELECT * FROM Persons VALUES
ORDER BY LastName DESC
(4,‘Naman', ‘Shah', ‘gandhinagar', ‘g
andhinagar')
2) INSERT INTO Persons
(P_Id, LastName, FirstName) VALUES
(5, ‘Amin', ‘Jay')
11. SQL Syntax & Statements
• UPDATE • DELETE
Syntax : UPDATE table_name Syntax : DELETE FROM table_name
SET
column1=value, column2=value2,...
WHERE some_column=some_value Example:
Ex. 1) DELETE * FROM Persons
2) DELETE FROM Persons
UPDATE Persons WHERE Lastname = ‘Rathod’
SET Address=‘Sector21',City=‘Gandhinagar'
WHERE LastName=‘Shah' AND
FirstName=‘Naman’ CAUTION:
DELETE cannot be undo.
13. Where to write this things??...
• Install java platform with JDBC API
• Install a driver
• Install DBMS (if u don’t have any)
• Set up Database
• Load drivers (In java program)
• Make connection (In java program)
• Write SQL statements in your program.
– E.g.
Statement stmt = con.createStatement();
(
stmt.executeUpdate "INSERT INTO COFFEES " +
"VALUES ('Colombian', 101, 7.99, 0, 0)");
