1. SQL

2. Introduction to SQL What is SQL?
When a user wants to get some information from a database file, he can issue a query.
A query is a user–request to retrieve data or information with a certain condition.
SQL is a query language that allows user to specify the conditions. (instead of algorithms)

3. Introduction to SQL Concept of SQL
The user specifies a certain condition.
The program will go through all the records in the database file and select those records that satisfy the condition.(searching).
Statistical information of the data.
The result of the query will then be stored in form of a table.

4. Create table command This command is use for creating a table.
Rules for creating tables
A name can have maximum upto 30 characters.
A-Z , a-z , 0-9 allowed
A name should be begin with an alphabet
The use of special character like _ allowed and also recommaended
SQL reversed words not allowed.(ex. create , select and so on.)

5. Create new table
CREATE TABLE TABLENAME (<ATTRIBBUTES> <DATATYPE> <SIZE>);
EX:
create table persons(P_ID number(10),LASTNAME varchar2(20),FIRSTNAME varchar2(20),ADDRESS varchar2(20),CITY varchar2(15));
Table Created.
Select * from persons;
P_ID
LASTNAME
FIRSTNAME
ADDRESS
CITY

6. Now Display all the table
Query :
Select * from tab;
Display list of tables.
Displaying Table Structure
Query :
DESC PRSONS;

7. INSERT DATA INTO TABLE SYNTAX :
INSERT INTO table_name VALUES (value1, value2, value3,...);
Now we want to insert values in table persons
QUERY
INSERT INTO persons values(1,’SHAH’,’CHINTAN’,’SATELLITE’,’AHMEDABAD’);
1 row created

8. INSERT multiple rows in table
QUERY
INSERT INTO persons values(&ID,’&LASTNAME,’&FIRSTNAME’,’&ADDRESS’,’&CITY’);
Enter value for ID : 1 .
1 row created
Press / and enter

9. VIEWING DATA IN THE TABLES
SELECT * FROM PERSONS;

10. Filtering Table Data Selected Columns And All Rows Syntax :
SELECT <columnname1>,<columnname2> FROM Table Name ;
Example :
SELECT P_ID , LASTNAME FROM PERSONS;
P_ID
LASTNAME 1
SHAH 2
PATEL 3
PANDYA 4

11. Filtering Table Data Selected Rows and All Columns Syntax :
SELECT * FROM <Table Name> WHERE <Condition> ;
Example :
SELECT * FROM PERSONS WHERE NAME=‘NITIN’;
P_ID
LASTNAME
FIRSTNAME
ADDRESS
CITY 3
Nitin
Pandya
Gandhinagar

12. Distinct Eliminating duplicate rows
-The DISTINCT clause removing duplicates from the result set.
-The DISTINCT clause can only used with select statements.
-SELECT DISTINCT Syntax
SELECT DISTINCT <COLUMNNAME1> FROM <TABLENAME>;

13. We use the following SELECT Statement
We use the following SELECT Statement. SELECT DISTINCT city FROM persons;
P_ID
LASTNAME
FIRSTNAME
ADDRESS
CITY 1
Chintan
Shah
Satellite
Ahmedabad 2
Sanjay
Patel
Gandhinagar 3
Nitin
Pandya
CITY
Ahmedabad
Gandhinagar

14. SORTING DATA IN A TABLE
Orcle allows data from a table to be viewed in a sorted orders.
The rows retrieved from the table will be sorted in either ascending or descending order.
The ORDER BY keyword is used to sort the result-set by specified column.
The ORDER BY keyword sort the records in ascending order by default.
If you want to sort the records in a descending order, you can use the DESC keyword.

15. SQL ORDER BY Syntax SELECT column_name(s) FROM table_name ORDER BY column_name(s) ASC|DESC
P_ID
LASTNAME
FIRSTNAME
ADDRESS
CITY 1
SHAH
CHINTAN
SATELLITE
AHMEDABAD 2
PATEL
SANJAY
GANDHINAGAR 3
PANDYA
NITIN
TALOD 4
VISHAL
GHATLODIA

16. We use the following SELECT statement: SELECT
We use the following SELECT statement: SELECT * FROM persons ORDER BY LASTNAME;
P_ID
LASTNAME
FIRSTNAME
ADDRESS
CITY 3
PANDYA
NITIN
TALOD
GANDHINAGAR 2
PATEL
SANJAY 4
VISHAL
GHATLODIA
AHMEDABAD 1
SHAH
CHINTAN
SATELLITE

17. ORDER BY DESC example SELECT * FROM persons ORDER BY LASTNAME DESC;
P-ID
LASTNAME
FIRSTNAME
ADDRESS
CITY 1
SHAH
CHINTAN
SATELLITE
AHMEDABAD 4
PATEL
VISHAL
GHATLODIA 2
SANJAY
GANDHINAGAR 3
PANDYA
NITIN
TALOD

18. DELETE Statement Removal of all ROWS -Syntax DELETE FROM PERSONS;
-All rows deleted

19. Question: - If I want to retrieve data of persons table.
What will happen?
What will be an answer?

20. UPDATING CONTENS OF A TABLE
The UPDATE command is used to change or modify data values in a table.
SQL UPDATE Syntax
UPDATING ALL ROWS
UPDATE <TABLENAME>
SET <COLUMNNAME1>=<NEW VALUE> , <COLUMNNAME2>=<NEW VALUE>;

21. Example Now we want to UPDATE LASTNAME in persons table UPDATE persons
SET LASTNAME=‘ABC’;

22. -Now, what will be effect? -How looks table(persons)
P_ID
LASTNAME
FIRSTNAME
ADDRESS
CITY 1
ABC
CHINTAN
SATELLITE
AHMEDABAD 2
SANJAY
GANDHINAGAR 3
NITIN
TALOD 4
VISHAL
GHATLODIA
UPDATE records Conditionally
UPDATE table_name SET columnname=value, columnname=value2 WHERE columnname=value;

23. Now we want to UPDATE CITY from Ahmedabd to Bombay, whose FIRSTNAME IS CHINTAN
UPDATE Persons
SET CITY=‘BOMBAY’
WHERE FIRSTNAME=‘CHINTAN’;
What will be result and how looks table?

24. -What will be result and how looks table?
P_ID
LASTNAME
FIRSTNAME
ADDRESS
CITY 1
SHAH
CHINTAN
SATELLITE
BOMBAY 2
PATEL
SANJAY
GANDHINAGAR 3
PANDYA
NITIN
TALOD 4
VISHAL
GHATLODIA
AHMEDABAD

25. MODIFY STRUCTURE OF TABLE
ADDING new columns in existing table.
Syntax
ALTER TABLE <TABLENAME>
ADD(<NEW COLUMNNAME><DATATYPE>(<SIZE>));

26. Now we want to ADD PINCODE fields in PERSONS table
Query
ALTER TABLE persons
ADD(PINCODE NUMBER(6));
OUTPUT: -
P_ID
LASTNAME
FIRSTNAME
ADDRESS
CITY
PINCODE 1
SHAH
CHINTAN
SATELLITE
AHMEDABAD 2
PATEL
SANJAY
GANDHINAGAR 3
PANDYA
NITIN
TALOD 4
VISHAL
GHATLODIA

27. EXERCISE TIME NOW INSERT/UPDATE PINCODE IN PERSONS TABLE.
Your table looks like this.
P_ID
LASTNAME
FIRSTNAME
ADDRESS
CITY
PINCODE 1
SHAH
CHINTAN
SATELLITE
AHMEDABAD
380015 2
PATEL
SANJAY
GANDHINAGAR
382051 3
PANDYA
NITIN
TALOD
382055 4
VISHAL
GHATLODIA
380009

28. MODIFY STRUCTURE OF TABLE
MODIFY columns in existing table.
Syntax
ALTER TABLE <TABLENAME>
MODIFY(<COLUMNNAME><NEWDATATYPE>
(<NEWSIZE>));

29. MODIFY(PINCODE VARCHAR2(10));
Now we want to MODIFY PINCODE data type from NUMBER TO VARCHAR2 in PERSONS table.
Query
ALTER TABLE persons
MODIFY(PINCODE VARCHAR2(10));
OUTPUT: -
TABLE ALTERED.

30. RENAMING TABLES SYNTAX :
RENAME <TableName> TO <NewTableName>
EXAMPLE :
RENAME PERSONS TO CLIENTS;
TABLE RENAMED

31. TRUNCATING TABLES DESTROYING TABLES EXAMPLE : TRUNCATE TABLE PERSONS;
Table Truncatd.
DESTROYING TABLES
EXAMPLE:
DROP TABLE PERSONS;
Table Dropped.