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If database is categorized in 4 different types likewise DBMS is also categorized in

4 different types depending on its supports.

If DBMS supports to store retrieve and modify the data of network database then it

will be termed as NDBMS

Likewise if DBMS supports hierarchal, relational or object relational database to

manipulate them, then they will be termed as HDBMS, RDBMS, ORDBMS, respectively

.

RDBMS

Data : Attribute

Information : Tupple or Row

Datafile : Table

Database : Databank/Data warehouse

It is basically a concept which is developed by a scientist by John E.F.Cord in 1970

June . In his concept code prescribes 12 different rules known as 12 cord Rule.

If any database software fulfills 6 or more than 6 rules of cord rules of Cord that

will be termed as RDBMS types Software and if any database software fulfills less than 6

rules then they will termed as DBMS.

Greater Than 6(RDBMS) Lessthan 6(DBMS)

Oracale 6,7 Foxpro

Access Dbase

SQL Server Foxbase

DB2 Paradox

Informix

Ingiris

A relational Model of Data For Large Shared Databank It is book when 12 cord rules are

described and it is a foreign edition.

RDBMS

RDBMS is nothing but the collection of 2 dimensional table or relation.

Department

Dept No. 10 20 30

Dname Sales Purchase Admin

Loc CTC BBSR RKL

Employee

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Emp No 1 2 3

Name X Y Z

Sal 5000 6000 7000

Dept. No 10 10 20

The above graphics shows the relational model of architecture where both the tables are

related using a common attribute called Dept No.

In relational model of architecture always the data is represented in different

modules where each modules is known as table and each table has a relationship with

another one Data Modularity has 2 advantages.

1. Data Redundancy will be less

2. Data Security will be high

ORDBMS

It is the extended version of RDBMS. The extra feature is the object feature. Any thing

stored in Object relational Database will be treated as one object.

**Note : The advantages of Object Relational Database over a relational database is

memory management is proper and coding is less.

Feature of RDBMS

Class, Object, Abstraction, Encapsulation, Polymorphism. Inheritance

Class

Class is nothing but a template style of a blueprint which does not have its physically

existence. It is nothing but the collection of properties & behaviors of similar types of

object.

Object

It is nothing but instance of a class which has its physical existence having some properties

and behaviors.

Abstraction

This is a concept through which one object essential features will be represented hiding the

background details. It leads to data hiding which leads data security.

Encapsulation

This is a concept through which the data member and the member function will be rapped

up, under one module where each module is known as a class.

Polymorphism

This is a concept through which one object can act differently in different different

circumstances.

Inheritance

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This is a concept through which one object property and behavior can be reused in another

object .

Advantages of ORDBMS over RDBMS

1. Support for User Defined Datatype.

2. Supports for Multimedia.

3. High Quality Server Feature

4. Fully Relational

As because object relational database supports object features. It supports user

defined data type that means user can declare its own data type and used it inside the

programme.

Object relational database supports multimedia files such as Jpg file,Gif, Bmp,

Avi, etc. That means object relational database not only stress conventional types of data

rather than it stores multimedia data type.

Object relational database is popular for its high quality server features. Itsupports 3 level security

1. Client Level

2. Network Level

3. Server Level

Apart from that object related database supports 512 petabytes data.

As because object related database is based on relational database. It supports maximum

rules. So it is known as fully relational.

Eg:- Oracle 8, Oracle 8i, Oracle 9i

Oracle 9i

Oracle provides two different languages to manipulate its database.

(1) SQL (Structure Query Language)

(2) PL SQL (Procedural Language Extension of SQL)

Though oracle provides two different languages to manipulate its database but none of

these languages belongs to oracle because.

(1) SQL is an ANSI standard language which is required to manipulate the database

interactivity. Interactivity means one command can be extended at one point of time.

As because SQL is an ANSI Standard Language it is not only meant to manipulate

Oracle Database rather than it is meant to manipulate any type of database currently

available.

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(2) Where as through PL SQL is pronounced as a language rather than it is a mechanism or

technology implemented on ORACLE Server to manipulate the database programme

i.e using SQL commands.

SQL

It is not a single language of its own rather than it is a combination of 5 different Sub

languages . Namely

1. DQL (Data Query Language)

2. DDL (Data Definition Language)

3. DML (Data Manipulate Language)

4. TCL (Transaction Control Language)

5. DCL (Data Control Language)

DQL

This is a sub language which is helpful to retrieve the data from table and show to the

user. Otherwise it is known as Data Retrieval Language. It provides a statement Called

Select.

DDL

It is otherwise known as (OML) Object Manipulate Language , which is required to

create and manipulate the object in the Oracle Database. Oracle provides 5 different

types of Object for customized DBMS. Table, View, Synonyms, Sequence, Index. To

create and manipulate above object . DDL Provides five different statements , Create,

Alter, Drop, Truncate , Rename,.

DML

DML otherwise is known as Record Manipulate Language (RML), Which is

required to manipulate the record of tables. To accomplish the job DML provides different

statements. Insert, Update, Delete.

TCL

This sub language is required to control the transaction (Insert, Update , Delete)

made by the user. When ever any transaction is made in Oracle table those record will

never be permanent unless or until a save command is issued or discard command is

issued . To accomplish the job TCL provides 3 different statements.

1. Commit

2. Rollback

3. Savepoint

DCL

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Oracle supports user concept or schema concept to protect the object from invalid users .

To create and manipulate those users DCL provides different statements.

1. Grant

2. Revoke

*Note :- Schema :- It is nothing but logical area which holds some physical object

protected by a password.

Oracle provides a environment which acts as an interface between the user and the

database and the interface i.e. known as SQL * PLUS. Whenever a command is issued

from SQL * Plus , it goes to database and database will process the data command and

send the output back to SQL *Plus.

*Note : The difference between an editor and the environment is the editors are the

application which are require to edit the text and doesnt have its own command . Where as

an environment is an application which is required to manipulate other application as well

as has its own command itself.

When ever an user log on to Oracle . It shows a logon screen having 3 different options .

1. User name2. Password

3. Host String

Host string is an option which is required when ever an user working on multi Server

Architecture.

Select

It is a power full query statements which is helpful to extract the data from one

table or more than one table.

Syntax of Select Statement

Select [Distinct] from

Select Statement can perform 2 jobs .

1. Selection

2. Projection

Projection can be posed in two different manner.

SQL>

OUTPUT

SQL * PLUS

ORCALE 9I

b b b

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1. Column wise Projection / Column Restriction

2. Row wise Projection / Row Restrictions

Column Restriction is a concept through which , those column are displayed which

are specified in the column list.

Eg: - select empno, ename,sal from emp;

Where as row restriction is a concept through which those record are displayed when a

condition is satisfied.

*Note : - * represents for all column of a table and each individual SQL commands re

terminated by ; .

Working with Column Alias (Duplicate Name of an Object)

Column is a concept though which an user can provide a duplicate name to an existing

column. Column Alias can be given in three different manner.Consider the EMP table in Scott Login.

1. SELECT EMPNO NO,ENAME NAME,SAL SALARY FROM EMP

2. SELECT EMPNO AS NO,ENAME AS NAME,SAL AS SALARY FROM

EMP

3. SELECT EMPNO NO,ENAME NAME,SAL SALARY FROM EMP.

*Note :- When ever an alias is represented in multiple words it has to put in double

quotes ( ).

COLUMN CONCATENATION

1. SELECT EMPNO || JOB FROM EMP

2. SELECT EMPNO || JOB AS JOBPROFILE FROM EMP

3. SELECET EMPNO || IS WORKING AS || JOB AS JOBPROFILE FROM

EMP.

*Note:- In oracle string type of values and date type of values are always represented

through ( )single quote.

ARITHMETIC OPERATION THROUGH SELECT STATEMENT OR WORKING

WITH VIRTUAL COLUMN.

Select Statements supports arithmetic operators to implement formula concept .The

outcome of formula is basically known as a virtual column which does not have its

physical existence.

Eg. 1) SELECT EMPNO,ENAME,SAL,SAL*1,SAL*.11,SAL*.12 FROM EMP

What Where

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2) SELECT EMPNO,ENAME,SAL,SAL*1 AS TA,SAL*.11 AS DA,SAL*.12

AS HRA FROM EMP.

SQL*PLUS

When ever a valid SQL Statement is issued from SQl prompt, it never goes to database

directly rather than it passes through a temporary memory to database and the temporary

memory is known as a BUFFER.

BUFFER

Buffer is nothing but an active temporary memory in client side RAM, which holds a

statement for a temporary period unless or until another statement is issued by the user or

the memory is explicitly deleted by the user.

Editor or Ed

The above commands are required to open the buffer memory through default

editor called NOTEPAD.

RUN or /

SQL>

SQL *PLUS

CLIENT SITE

BUFFER(NOTEPAD)

(AFIEDT.BU

F)SERVERDatabase

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The above command is used to run buffer memory.

SAVE

To save a statement in a file permanently

Syntax :- SAVE

Eg.- SAVE END

An user can store statement for a permanent period in form file those filr a re

basically known as SCRIPTFILES . The extension of these type of files are known as

.SQL.

START

To execute the script file.

Syntax : - START

Or

@

The above command is used to run a script file.START command can perform 2 jobs.

1. Load the statement from the hard disk to buffer

2. RUN the buffer.

GET

The above command required to load the statement from the hard disk to the buffer

memory.

Syntax: Get

Clear

Clear the buffer

Syntax : Clear Buffer or Cl Buff

Show

Show the Current Username

Syntax : Show User.

Host

It is a SQL * Plus command required to jump from SQL * Plus to DOS Envirnmnet.

SAVE

Save a file in different location

Syntax : Save d:\aa.sql(Path Location)

Difference Between SQL and SQL * Plus

SQL SQL*PLUS

1. It is an Ansii Standard Language required

to manipulate the database

1.It is an environment proprietary of Oracle

b

b

b

b

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2. SQL Commands cannot be abbreviated 3.These commands can be abbreviated

Eg: Clear screen (Cl scr )

3.SQl Command always terminated by a ; 3. No optional character is used to terminate

SQL *PLUS Commands.

4. SQL Command always passes through

the buffer to database for execution.

4. No buffer memory is used fro SQL * Plus

commands

ROW RESTRICTION THROUGH SELECT STATEMENT

It is a concept implemented on select statement to restrict the record depending on a

condition . To implement condition select statement provides a clause called WHERE.

Syntax of SELECT using WHERE

Select

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From

[Where ];

To restrict records depending on a condition Oracle provides 3 different types of

operators.

1. Arithmetic Operator

2. Relational Or Comparison Operator.(>,=,2000 AND SAL

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WHERE JOB IN (SALESMAN,ANALYST,..,)

LIKE

It is a powerful query operator, which is required to extract the data from the table,

depending upon a character position. This operator is meant for character types of values or

date types of values. It provides the wild card character to accomplish the job.

Wild Card Character

% - It represents multiple characters

_(Underscore):- It represents a single character.

Eg : SELECT * FROM EMP

WHERE ENAME LIKE S%; (First Character)

2. SELECT * FROM EMP

WHERE ENAME LIKE %S (Last Character)

3. SELECT * FROM EMPWHERE ENAME LIKE S% OR ENAME LIKE %S


WHERE ENAME LIKE __ i %H (3rd character i and last character H

NOT LIKE

Eg : SELECT * FROM EMP

WHERE ENAME NOT LIKE S% AND ENAME LIKE %S

1. DATE LIKE %82

2. DATE LIKE %FEB

IS NULL

Null is a special kind of value which is Unassigned or Inapplicable To extract the

value from a table depending upon the NULL value . Oracle provides an operator called Is

Null.

Eg: SELECT * FROM EMP

WHERE COMM IS NULL;

JOIN

It is a mechanism or a technology implemented on select statement to extract the

data from multiple tables. To extract the data from multiple tables ,the tables must have a

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relationship depending upon the relationship of tables JOIN is categorized in 4 different

types.

1. Equi Join

2. Non Equi Join

3. Self Join/Inner Join

4. Outer Join

1. EQUI JOIN

It is a type of join , which will extract the data from multiple tables when a

common attribute is available.

TABLE EMP

(CHILD)

EMPNO NAME SAL DEPTNO

1 X - 20

2 Y - 10

3 Z - 204 A - 30

5 B - 10

TABLE DEPT

(MASTER)

DEPT NO DNAME LOC

10 SALES CTC

20 PUR BBSR

30 ADMIN RKL40 FIN BPD

The above graphic shows both the tables have a common attribute called

DEPTNO . To extract the data from above tables the user can use EQUI-JOIN.

Syntax

SELECT TBLE1.COL,TABLE1.COL,TABLE2.COL,TABLE 2.COL..N

FROM TABLE1,TABLE2

WHERE TABLE1.COL=TABLE2.COLEg: SELECT EMP.EMPNO,EMP.ENAME,EMP.SAL,

DEPT.DNAME,DEPT.LOC

FROM EMP ,DEPT

WHERE EMP.DEPTNO=DEPT.DEPTNO;

**Note : A table name preferred with the column name is optional in nature , but is

mandatory when ever a common attribute is extracted.

Eg. SELECT EMPNO,ENAME,SAL,DANME,LOC,DEPT.DEPTNO,

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FROM EMP,DEPT

WHERE EMP.DEPT NO=DEPT.DEPTNO

OUTER JOIN

It is a type of join which will extracted the data from multiple tables weather the

condition is satisfied or not satisfied . In other words Outer Join is a type of join which will

extract all the data from multiple tables.

Eg. : Write a statement which will display empno,name ,sal , deptno, and location of

those who is working in a particular department as well as display those department

information under which no person are working.

SELECT EMPNO,ENAME,SAL,DNAME,LOC,

FROM EMP, DEPT


NON EQUI JOIN

It is type of join which will extract the data from multiple tables when ever nocommon attribute is available but there must be a relationship.

EMPNO NAME SAL DEPTNO GARDE LSAL HSAL

1 X 7500 1 700 1200

2 Y 2500 2 1201 2000

3 Z 950 3 2001 5000

4 A 3800 4 5001 8000

5 B 850 5 8001 9999

The above graphics shown both the tables have no common attributes but there is

an internal relationship using High salary and Low Salary . High salary of salgrade table to

extract the data from above tables the user can use non equi join.

Eg. Write a statement to display empno, ename, salary, grade

SELECT EMPNO,ENAME,SAL,GRADE,DNAME,LOC

FROM EMP ,SALGRADE,DEPT

WHERE SAL BETWEEN LOSAL AND HISAL

2. Write a statement which will display empname,salary,grade,deptname,and loc of

those employee whose job is salesman

SELECT EMPNO,ENAME,SAL,GRADE,DNAME,LOC

FROM EMP ,SALGRADE,DEPT


AND EMP.DEPTNO = DEPT.DEPTNO

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AND JOB= SALESMAN;

WORKING WITH TABLE ALIAS

It is a concept or mechanism required to provide a duplicate name to an existing

table. Table alias is meant to provide short name instead of using object. This concept only

implemented for JOIN statement.

Eg: SELECT E.EMPNO,E.ENAME,E.SAL,D.DNAME,D.LOC

FROM EMP E,DEPT D

WHERE E.DEPTNO=D.DEPTNO;

SELF JOIN OR INNER JOIN

Self join is a concept or mechanism where a table is joined with itself to get the

output.

EMPNO NAME MGR(EMPNO) DEPTNO

1 X 2 -

2 Y 3 -

3 Z - -4 A 3 -

5 B 4 -

From this table

Y is the manger of X, Z is manager of Y, Z is manager of A, A is manager of B, Z has no

manager (Head)

Eg. 1. SELECT W.NAME || IS WORKING|| M.NAME

FROM EMP W, EMP M

WHERE W.MGR=E.EMPNO;

2. SELECT EMP.EMPNO, EMP.ENAME, EMP.SAL, EMP.DNAME, EMP.LOC

FROM EMP,DEPT


3. Deficiency (+) or Child table

SELECT EMPNO, ENAME,SAL,GRADE,DNAME,SAL

FROM EMP,SALGARDE,DEPT


AND EMP.DEPTNO(+) = DEPT.DEPTNO;

Predefined Function In Oracle

Procedure Not value returned

Function Value Returned

SQL provides a series of predefined functions to enhance the capacity of SQL

statements these functions are categorized in 2 different types.

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1. SINGLE ROW

2. MULTI ROW

SINGLE ROW

It is a function which will accept one value as a argument & returns one value per

row.

MULTI ROW

Where as multi row function are those functions which will accepts multiple values

as an argument and returned one value per row.

CASE CONVERSION

This function are required to convert a character or a string from one cas to

another . The functions are

LOWER ( )

UPER ( )

INITCAP ( )

Eg. : SELECT LOWER(ENAME) FROM EMP;

**Note : The user can pass 2 types of values as an argument in a single row function

1. Column name

2. Static Value as an argument

**Note : When ever a static value is passed to single row function , the output will be

displayed that may no of times , the no of records available inside the table.

Eg : SELECT LOWER (ORISSA) FROM EMP;

FUNCTION

SINGLE ROW MULTI ROW

CHRACTER NUMBER DATE CONVERSION

CASE CONVERSION CHARACTER MANIPULATION

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Here the output will display 14 no of times. Test a single row function oracle

provides a predefined tba;e called dual , which is having one column DOMY one value as

X

Eg: SELECT LOWER(ORISSA) FROM DUAL;

CHARACTER MANIPULATION

These functions are required to manipulate the character type of values or string

type of values and the functions are

1. CONCAT ( )

2. SUBSTR ( )

3. INSTR ( )

4. LTRIM ( )

5. RTRIM ( )

6. LENGTH ( )

CONCAT ( )

This function is required to concatenation 2 strings or 2 columns.

Eg. : SELECT CONCAT (ENAME,JOB) FORM EMP

SELECT CONCAT (ENAME, CONCAT(WORKING AS,JOB)) FROM EMP;

SUBSTR

This function is required to extract the specific no of characters from a specified

string (String character include no of characters)

Syntax: SELECT (STRING |COLUMN ,STARING POINT OF STRING | [NO OF

CHARACTERS] );

Eg: SELECT SUBSTR(ORISSA,2,4) FORM DUAL;

INSTR (Inside the string)

This function is required to display a character position inside a specific string. If

the character is not available it will return 0 and if it is redundant, it will display first

character position.

Synatx : INSTR(STRING | COL, SINGLE CHARACTER)

LENGTH ( )

It will display the length of a string or length of a column values.

Eg : SELECT LENGTH (ORISSA) FROM DUAL;

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LTRIM ( ) /RTRIM ( )

This features are always require to truncate the blank space from left and right side

of the string.

Eg: SELECT LENGTH (LTRIM(ORISSA))FROM DUAL;

NUMBER FUNCTION

These functions are required to manipulate numeric values.

1. ROUND

2. TRUNCATE

3. MOD

ROUND

This is a function required to round a floating values.Eg: SELECT ROUND (45.378) FROM DUAL; 45,

IF THE NUMBER AFTER DECIMAL IS

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7. TRUNCATE ( )

ADD_MONTHS ( )

It is a function which is required to add a specific no of month to a specify date.

Eg: SELECT ADD_MONTHS (25-AUG-05,6 ) FROM DUAL;

MONTHS_BETWEEN ( )

This function is required to display approx month difference between two specify

dates.

Eg: SELECT MONTHS_BETWEEN (25-SEP-05,25-AUG-05) FROM DUAL;

LAST_DAY ( )

It is a function to view the last day of months date.

Eg: SELECT LAST_DAY(25-AUG-05)FROM DUAL;

NEXT_DAY

This is a function is required to display next day of the week date.

Eg: SELECT NEXT_DAY(25-AUG-05, FRIDAY) FROM DUAL;

SYSDATE

SELECT SYSDATE FROM DUAL;

SELECT CURRENT_ DATE FROM DUAL

ROUND

This function is required to round a date month wise or year wise. If the date is

rounded by month , it will check the day part. If the date is rounded by Year , it will check

the month part.

Eg: SELECT ROUND(TO_DATE(25-AUG-05), MONTH)FROM DUAL;

*Note : To_date is conversion function which is required to convert a string date to

actual date.

>=JULY 1ST DAY OF 1ST MONTH OF NEXT YEAR

=16- 1ST DAY OF NEXT MONTH

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Eg: SELECT TRUNC (TO_DATE( 25-AUG-05 ), MONTH)FROM DUAL;

SELECT TRUNC (TO_DATE( 25-AUG-05 ), YEAR)FROM DUAL;

CONVERSION FUNCTION

It is a type of function which is required to convert a value from one data type to

another data type.

TO_NUM ( ) TO_DATE ( )

NUMBER CHARACTER DATE

TO_CHAR( ) TO_CHAR( )

TO_CHAR ( )

This function is required to convert date to character or number to character.

Syntax : To_Char (Date | Number , FMT);Date to Character

Date to character formatting strings are :

DY : Abbreviated Character form of the Day of the Week.

DAY : Full character form of the day of the week

DD : Numeric representation of the day of the month between 1 to 31st

DDTH : Numeric representation of the day of the month in the period

DDTHSP : Character representation of the day of month dth format.

MM : Numeric representation of month between 1 to 12

MON : Abbreviated character of the month

MONTH : Full character form of the month

YY : Display the Year Part

YYYY : Display the year in centurion format.

Eg: SELECT TO_CHAR(TO_DATE(22-JAN-05),DDTH MON YY)FROM DUAL;

SELECT TO_CHAR (TO_DATE (22-JAN-05),DDTH-MON-YY)FROM DUAL;

Number to Character:

$ : Prefix $ as a symbol

9. : Represents the no in character format

, : Thousand separator

. : Decimal Notation

L : Prefix as a local currency style.

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TO_NUMBER

This function is required to convert string number to actual number

Eg: SELECT 10 FROM DUAL;

SELECT TO_NUMBER(10) FROM DUAL;

MULTI-ROW FUNCTION

This function is a type of function which will accept multiple values as an argument

& return one value per garoup & the functions are

1. SUM ( )

2. MAX ( )

3. MIN ( )

4. AVG ( )

5. COUNT ( )

Eg: SELECT SUM(SAL), MAX(SAL), MIN(SAL), AVG(SAL) FROM EMP;

The above example will display sum(sal), max(sal), min(sal), and avg(sal) of

employee table where employee table is treated as a group.

WORKING WITH GROUP BY CLAUSE

Group by clause is a clause of select statement used to logically segregate the table

data in different different block. This clause is only implemented for group functions

(Multi-Row Functions).

Syntax of select using group by clause.

Select

From

[Where ]

[Group by [COL_NAME,N]

Eg: SELECT SUM(SAL), MAX(SAL), MIN(SAL), AVG(SAL) FROM EMP GROUP

BY DEPTNO;

The above example will display department wise sum(sal), max(Sal), min(sal),

avg(sal).

*Note : The user must use those columns in the group by clause the column which

have hugely duplicate values.

The user can use a column in the select list if the column is used in the group by

clause.

Eg: SELECT ENAME , SUM(SAL), MAX(SAL),AVG(SAL) FROM EMP GROUP

BY ENAME;

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The above example is an example of single column wise grouping

WORKING WITH MULTICOLUMN WISE GROUPING

Eg: SELECT DEPTNO, JOB, SUM(SAL), MAX(SAL), MIN(SAL) FROM EMP

GROUP BY DEPTNO, JOB.;

The above example will display sum(sal), max(sal) & min(sal).

COUNT ( )

This function is required to count the no of records of a group or no of values of a column.

Count function can accept 2 types of argument

(i) Count (*)

(ii) Count (Col.name)

Eg: Select count(*) from emp;

Select count(ename) from emp;

Question: Write a statement which will display department , job, sum (sal), min(sal),

max(sal) & the no of the persons working under each group.

Ans. SELECT DEPTNO,JOB,SUM(SAL),MIN(SAL), MAX(SAL),COUNT(*)

FROM EMP GROUP BY DEPTNO,JOB ;

WORKING WITH HAVING CLAUSE

HAVING clause is a clause of select statement which is required to restricted the

group depending on a condition. The difference between WHERE & HAVING is where

meant for row restriction where as HAVING is meant for group restriction.

SYNTAX OF SELECT USING HAVNING CLAUSE

SELECT

FROM

[WHERE ]

[GROUP BY ]

[HAVING < GROUP CONDITION>]

*Note : Select statement is nether case sensitive nor syntactical sensitive but select

statement is clause sensitive always.

Eg: SELECT DEPTNO , JOB, MAX(SAL), MIN(SAL), COUNT(*)

FROM EMP

WHERE DEPTNO 2000;

WORKING WITH ORDER BY CLAUSE

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ORDER BY clause is last of select statement which is required to arrange the

records in a proper manner either ascending or descending wise . To accomplish the job it

provides 2 pseudo columns. Ascending & Descending. The default order is ascending.

Eg: SELECT * FROM EMP ORDER BY DEPTNO;

SELECT * FROM EMP ORDER BY DEPTNO,SAL DESC;

The above example is an example of column wise ordering.

SYNTAX OF FULL FLEDGE SELECT STATEMENT

SELECT

FROM

[WHERE ]

[GROUP BY ]

[HAVING ]

[ORDER BY [ASC | DESC]];

SUB-QUERY

Sub query is a mechanism or technology implemented on select statement whenever a

condition value to an known to an user.

The advantage of sub query is to display the output whenever a condition value is

to known. Sub query has two different parts.

(i) Inner Query

(ii) Outer Query

Inner query is query which is always executed first to evaluate the condition value& provide the value to the outer query for the processing.

Where as outer query is a query which is responsible to accept the value from inner

query & display the output.

Depending on the value return from inner query to outer query sub query is

categorized in 2 different types.

1. Single Row Sub Query

2. Multi Row Sub Query

Single Row Sub Query

It is type of sub query where the inner query return one value to alter query

for processing.

Eg: Display those record whose salary is greater than Blakes Salary.

Where as multi row sub query is a sub query where inner query return more

than one value to outer query for processing.

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Eg: Display those record whose salary is greater than Blakes salaray

Where as multi row sub query is a sub query where inner query return more than one value

to outer query for processing.

Eg; Display those record whose salary is greater than all salary of department 30.

Syntax Of Subquery

SELECT

FROM

WHERE OPERATOR

(SELECT COL.NAME FROM WHERE );

*Note: The syntax of single row subquery and multi row subquery is same but the user

can identify the subquery from its operator . The single row subquery operators are >,

< , =, < >, =

Multi row subquery operators are :-

IN, >ANY, ALL, (SELECT SAL FROM EMP WHERE ENAME=BLAKE;


WHERE JOB=(SELECT JOB FROM EMP WHERE ENAME=ALEN)

AND ENAME ALEN;

3. Write a statement which will display those record whose salary is greater than

smiths salary & job must be same as ford.

SELECT * FROM EMP

WHERE SAL >(SELECT SAL FROM EMP WHERE ENAME=SMITH)

AND JOB = (SELECET JOB FROM EMP WHERE ENAME=FRD);

4. Write a statement which will display those records whose salary is greater than

SMITHs salary & less than BLAKE.

SELECT * FROM EMP

WHERE SAL>(SELECT SAL FROM EMP WHERE ENAME =SMITH)

AND SAL < (SELECT SAL FROM EMP WHERE ENAME=BLAKE);

FOR MULTI ROW SUBQUERY

1. Write a statement which will display those records whose salary is greater than all

salary of department 30.

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SELECT * FROM EMP

WHERE SAL >ALL(SELECT SAL FROM EMP WHERE DEPTNO=30);

2. Write a statement which will display the records whose job is same as any job of

Deptno 30.

SELECT * FROM EMP

WHERE JOB =ANY(SELECT JOB FROM EMP WHERE DEPTNO=30)

AND DEPTNO30;

*Note Any operator is same as IN Operator

3. Write a statement which will display records whose salary is greater than ANY

salary of deptno 30.

SELECT * FROM EMP WHERE SAL >ANY(SELECT SAL FROM EMP `

WHERE DEPTNO=30)

**Note : >any means >(Minimum Value of List)

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1. SELECT * FROM EMP WHERE DEPTNO=&DEPTNO

ENTER VALUE FOR DEPTNO

SESSION TYPE SUBSTITUTION VARIABLE :

1. SELECT * FROM EMP WHERE DEPTNO=&&DEPNO

Once assigned cannot be changed

It can be changed by

UNDEFINE DNO

Reassign the session substitute variable

DEFINE DEPNO=20

**Note : Define and undefine are 2 SQL * PLUS command required to reassign and

destroy a session type substitution variable.

REPORTING THROUGH SELECT STATEMENT:-

Reporting is nothing but customized representation of data. In SQL reporting canbe possible in 2 different manners.

1. Column Wise Formatting

2. Table wise Formatting

Examples :

Column ename heading name

Column sal heading Salary

Column comm heading commission

DDL

ALTER

Syntax to Alter a Table (Add or Modify)

ALTER TABLE

ADD | MODIFY (COL_NAME DATATYPE (SIZE),[COL_NAME DATATYPE

(SIZE),..N]);

Example

1. ALTER TABLE MYEMP

ADD (JOB VRCHAR2(20));


MODIFY (NAME VARCHAR2(40));

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**Note :- To add a new column , to delete an existing column or to change the size

of a column the table may or ,may not contain the data, But to change the data type

of a column , the column must be blank.

DELETE

Syntax :

ALTER TABLE

DROP COLUMN ;

The above syntax required to delete a single column from the existing table

structure

Delete Multiple Column

ALTER TABLE

DROP (COL1,COL2,..N)Example


DROP COLUMN JOB;


DROP (NAME ,SAL);

Deleting a table from database physically :-

Syntax :

DROP TABLE ;

In Oracle 8i Once Table is deleted from system we can range the table in proper

manner by using the following statement.

@DEMO BLD

Deleting all records physically from a table remains structure using truncate.

Syntax :

TRUNCATE TABLE

Example :

Truncate table systab;

Renaming a table using Rename

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Syntax :

RENAME TO

Example :

Rename systab to myemp;

CONSTRAINT

Constraint are nothing but rules or restrictions imposed on individual column to

avoid invalid data entry.

Oracle provides 5 different types of constraints to avoid invalid data entry.

1. Primary Key

2. Not Null

3. Unique

4. Check

5. Foreign Key

Primary Key :

Enforces No Null and No Duplicate Value to a column

Not Null :

Enforces No Null value to column but it can accept duplicate Value.

Unique :

Enforces no duplicate value to a column but can accept Null Value.

Check :

This always checks a condition before entering value to a column.

Foreign Key :

The constraint which is helpful to make a relationship between two or more tables

using common attribute.

Foreign key always references to same tables primary key or another tables

primary key to make a relationship.

Foreign Key is just opposite of primary key i.e. it can accept duplicate values as

well as Null Values.

Foreign Key supports the concept ofReferential integrity.

Imposement Of Constraints

A constraint can be exposed to individual column during design in two different

levels

1. Column Level

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2. Table Level

Column Level :

Column Level constraints are those constraints which are imposed on those

columns just after the column defining.

Table Level :

It is those constraints which are imposed on individual column after all column

definition during table design.

**Note : The difference between column Level and Table Level constraints i.e

In column level maximum one constraint can be imposed to a single column and

not null can be used here. In Table Level multiple constraints can be imposed on a

single column. Here we cannot use the Not Null.

COLUMN LEVEL CONSTRAINT :-

Syntax :

CREATE TABLE

(COLUMN NAME DATATYPE(SIZE) [CONSTRAINT ] ,

COLUMN NAME DATATYPE(SIZE) [CONSTRAINT ] ,

-------------------------------------------N);

Example :

Q1. Design the following table having the following attribute and constraint.

T_NAME : MYEMPConstraints

EMPNO : NUMERIC(4) PRIMARY KEY

NAME : VARCHAR2(20) NOT NULL

SAL : NUMERIC(7,2) CHECK (SAL BETWEEN 2000 AND 5000)

JOB : VARCHAR2(20) UNIQUE

Ans.

CREATE TABLE MYEMP

(EMPNO NUMBER(4) CONSTRAINT MYEMP_EMPNO_PK PRIMARY KEY,

NAME VARCHAR2(20) CONSTRAINT MYEMP_NAME_NT NOT NULL,

SAL NUMBER (7,2) CONSTRAINT MYEMP_SAL_CHK CHECK (SAL BETWEEN 2000 AND 5000),

JOB VARCHAR2(20) CONSTRAINT MYEMP_JOB_UK UNIQUE );

TABLE LEVEL CONSTRAINT :

Syntax :

CREATE TABLE

(COL_NAME DATATYPE (SIZE),

COL_NAME DATATYPE (SIZE),

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N

CONSTRAINT (COL_NAME),

CONSTRAINT (COL_NAME);

.N;

Example :

T_NAME : MYEMP

CONSTRAINTS

EMPNO : NUMERIC(4) PRIMARY KEY

NAME : VARCHAR2(20) NOT NULL

SAL : NUMERIC(7,2) CHECK (SAL BETWEEN 2000 AND 5000)

JOB : VARCHAR2(20) UNIQUE

Q1. Design the above table with same attribute using table level.

CREATE TABLE MYEMP(EMPNO NUMBER(4),


SAL NUMBER(7,2),

JOB VARCHAR2(20),

CONSTRAINT MYEMP_EMPNO_PK PRIMARY KEY(EMPNO),

CONSTRAINT MYEMP_SAL_CK CHECK(SAL BETWEEN 2000 AND 5000),

CONSTRAINT MYEMP_JOB_UK UNIQUE(JOB))

FOREIGN KEY

Syntax :

CREATE TABLE

(COL_NAME DATATYPE(SIZE),

COL_NAME DATATYPE(SIZE)

..(N)

CONSTRAINT FOREIGN KEY (COL_NAME)

REFERENCES (COL_NAME)),.;

Design The Following Tables :

T_NAME : MYDEPT

DEPTNO : NUMBER (4)

DNAME : VARCHAR2(20)

LOC : VARCHAR2(20)

2. T_NAME : MYEMP

EMPNO : NUMBER(4)

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NAME : VARCHAR2(20)

SAL : NUMBER(7,2)

MGR : NUMBER(4)

DEPTNO : NUMBER(4)

CONSTRAINTS

DEPTNO : PRIMARY KEY

DNAME : NOT NULL

CHECK (SALES,PURCAHSE,ADMIN)

LOC : NOT NULL

CHECK (CTC,BBSR,RKL)

2. EMPNO : PRIMARY KEY

NAME : NOT NULL

SAL : NOT NULL

CHECK (2000 -10,000)

MGR : FOREIGN REFERENCES MYEMP(EMPNO)

DEPTNO : FOREIGN REFERENCES MYDEPT(DEPTNO)

TABLE CREATION :

1. CREATE TABLE MYDEPT

(DEPTNO NUMBER(4),

DNAME VARCHAR2(20) CONSTRAINT MYDEPT_DNAME_NT NOT NULL,

LOC VARCHAR2(20) CONSTRAINT MYDEPT_LOC_NT NOT NULL,

CONSTRAINT MYDEPT_DEPTNO_PK PRIMARY KEY(DEPTNO),

CONSTRAINT MYDEPT_DNAME_CK CHECK(DNAME IN('SALES','PURCHASE','ADMIN')),

CONSTRAINT MYDEPT_LOC_CK CHECK(LOC IN('CUTTACK','BHUBANESWAR','ROURKELA')))

2. CREATE TABLE MYEMP

(EMPNO NUMBER(4),


SAL NUMBER(7,2) CONSTRAINT MYEM_SAL_NT NOT NULL,

MGR NUMBER(4), DEPTNO NUMBER(4),

CONSTRAINT MYEMP_EMPNO_PK PRIMARY KEY(EMPNO),

CONSTRAINT MYEMP_SAL_CK CHECK(SAL BETWEEN 2000 AND 10000),

CONSTRAINT MYEMP_MGR_FK FOREIGN KEY (MGR) REFERENCES MYEMP(EMPNO),

CONSTRAINT MYEMP_DEPTNO_FK FOREIGN KEY(DEPTNO) REFERENCES MYDEPT(DEPTNO))

DATA DICTIONARY / SYSTEM CATALOG

1. To see the name of the existing tables in the current user login

SELECT TABLE _NAME FROM USER_TABLES

2. To see the structure of the existing tables

DESC USER_TABLES

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3. To see the name of the existing constraints in the current user login

SELECT CONSTRAINT_NAME FROM USER_CONSTRAINTS

4. To see the name of the constraints with the table name

SELECT CONSTRAINT_NAME,TABLE_NAME FROM

USER_CONSTRAINTS

5. To see the name of the constraints with the table name and status

SELECT CONSTRAINT_NAME,TABLE_NAME,STATUS FROM

USER_CONSTRAINTS

6. SELECT CONSTRAINT_NAME,TABLE_NAME,STATUS FROM

USER_CONSTRAINTS

WHERE TABLE_NAME='MYEMP'

7. Want to see the range of check constraint

SELECT CONSTRAINT_NAME,TABLE_NAME,SEARCH_CONDITION

FROM USER_CONSTRAINTSWHERE TABLE_NAME='MYEMP'

Implicit naming convention of a constraint

If no constraint name is given by a user at table design by default system will provide a

constraint name which look like SYS-C005001.

**Note : A constraint can be deleted by 2 different manner

(i) Explicitly using alter command.

(ii) Implicitly when ever a table is being dropped.

DML/RML

Required to manipulate records of a table to accomplish the job DML provides 3

statements

1. INSERT

2. UPDATE

3. DELETE

1. INSERT

Syntax :

INSERT INTO [OL1,COL2N]

VALUES(VALUE1,VALUE2,N);

The above example is a simple insertion where the user remember the column name and

their sequences.

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Date Insertion With Column List :

Example : INSERT INTO MYEMP(SAL,EMPNO,NAME) VALUES

(3000,2,'BBSR')

Insertion Of Null Value to a Column :

Null value can be entered to a column in two different manners.

1. Explicitly using NULL key word

2. Implicitly using column specification.

Explicitly :

INSERT INTO MYEMP VALUES(1,AAA,NULL);

Implicitly :

INSERT INTO MYEMP(EMPNO,NAME)VALUES (1,AAA);

INTERACTIVE INSERTION :

INSERT INTO MYEMP VALUES(&EMPNO,&NAME,&SAL);

UPDATING A RECORD USING UPDATE :

Syntax :

UPDATE

SET COL_NAME =VALUE [,COL_NAME=VALUEN]

[WHERE ]

Example :

UPDATE MYEMP

SET SAL =500

WHERE SAL IS NULL;

**Note : If where clause is omitted from the update statement , it will update a the

values of specific columns.

Question :

Write a statement which will updated the employee salary of employee no 3

to Blake salary of employee table.

Answer :

UPDATE MYEMP

SET SAL= (SELECT SAL FROM EMP WHERE ENAME = BLAKE

WHERE EMPNO=3;

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UPDATING MULTIPLE COLUMN VALUE :-

Example :

UPDATE MYEMP

SET NAME= kkk, SAL =5000

WHERE EMPNO=4;

DELETE :

SYNTAX :

DELETE FROM

[WHERE ];

If where clause is omitted from delete statement , it will delete all the records from the

table.

Example :

DELETE FROM MYEMPWHERE EMPNO=4;

CREATING A TABLE USING QUERY STATEMENT

Example :

CREATE TABLE SYSTAB

AS SELECT * FROM EMP;

**Note : Whenever a table is copied using query statement only not null constraint is

copied to the destination table not all constraints.

COPY THE STRUCTURE OF TABLE EXCEPT DATA

Example :

Create table system

as select * from emp

where 1=2;

TCL

In oracle database whenever a transaction is made , the transaction will never be

save permanently unless and until a save command is issued or discard command is issued.

To do so TCL provides 3 statements.

1. Commit (Save)

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2. Roll Back (Discard)

3. Save Point

TCL MECHANISM

Whenever a DML command is issued from SQL prompt, just before the DMLoperation is made , automatically a temporary memory is created inside the server whihjc is

known as ROLLBACK SEGMENT and the table on which DML operation is going to be

made will be copied temporary to the roll back segment which is known as SNAPSHOT.

Whenever a commit command I issued in SQl prompt , the roll back segment along

with the snap shot will be deleted and records transacted t the main table will ve

permanent.

If a Roll Back command is issued from SQL prompt, the snapshot available in Roll

Back segment will again be copied to its original location with the old data by deleting the

Roll back Segment.

**Note : The data once committed cannot be Roll Back and once rolled back cannt be

committed.

Example :

INSERT INTO MYEMP

VALUES(..);

COMMIT;

INSERT INTO MYEMP

VALUES(..);

ROLLBACK;

ROWID :

Required to manipulate duplicate record.

Example :

SQL * PLUS ROLL BACK SEGEMNT TEMPORARY MEMORY (Snapshot)

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SELECT ROWID FROM EMP;

SAVE POINT

Savepoint is nothing but a logical pointer which is given to individual transaction or

group of transaction made by an user.

Savepoint is only applicable for rollback purpose. Rollback to a particular point

does not mean, the above transactions are committed.

Rollback to a particular point excluding of that point.

Example :

Empno Name Sal

1 AAA 7800

INSERT INTO MYEMPVALUES (2,BBB,5000)

SAVEPOINT A;

INSERT INTO MYEMP

VALUES (3,CCC,8000)

SAVEPOINT B;

INSERT INTO MYEMP

VALUES (4,DDD,6000)

SAVEPOINT C;

ROLLBACK TO B /*DISCARD C*/

ROLLBACK /*DISCRAD A & B*/

IMPLICIT COMMIT & IMPLICIT ROLLBACK

The above example shows explicit commit and explicit rollback of data. In sme

cases the data is automatically committed or automatically rolled bak by the servers itself

which is basically known as AUTO COMMIT & AUTO ROLLBACK.

In the following circumstances the data is automatically committed;

1. Whenever an user exit out of SQl * Plus normally after any transaction.

2. Whenever a DDL or DCL command is used after any DML operation.

In the following circumstances the data is automatically Rolled Back;

1. Whenever an user exit out of SQL *PLUS abnormally after any transaction.

2. During system Crash.

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SET AUTOCOMMIT ON :

Valid upto

1. Whenever user exit of SQL * plus

2. Set Autocommit Off

Difference Between Rollback Segment & Buffer :

Rollback Segment Buffer

1. Stores the table called snapshot Stores the SQl Statement

2. Server side Client side

OBJECT

VIEW :

1. View is nothing but a logical subset of a data which is based on one table or more

than one tables.

2. The advantages of view is to protect the table structure from invalid users.

3. View is otherwise known as virtual table

4. The table based on which the view is created is known as the Base table.

5. Depending on the base table view is categorized into 2 different types.

I. Simple View

II. Complex View

Simple View is a type of view which is based on a single table or whose base table is one.

Complex View is a type of view which is based on multiple table or whose base table is

multiple.

Syntax :

CREATE [OR REPLACE] [FORCE | NOFORCE] VIEW

AS

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[WITH CHECK OPTION]

[WITH READ ONLY];

**Note : View neither contains the structure nor data of a table rather than it contains

only select statement of the base table. But the structure cannot be manipulated by the

user.

Example :

CREATE OR REPLACE VIEW MY VIEW

AS SELECT * FROM MYEMP;

The above example create a simple view which is based on myemp table.

Any record can be inserted, updated, deleted or selected through the view to the base table.

View can be based on a condition

Example :

CREATE OR REPLACE VIEW MYVIEW

AS SELECT * FROM MYEMP

WHERE DEPTNO=20;

In the above example a view will be created based on condition. If a view is based

on condition and record can be inserted through the view to the base table.

But those records are updated deleted and selected on which condition the view is

created.

Restricting Insertion Depending on condition using with check option

Example :

CREATE OR REPLACE MYVIEW


WHERE DEPTNO=20

WITH CHECK OPTION ;

We cannot insert the values like these (1, AAA , 67000, 10);

Through the above example a view will be created which meant for deptno=20

Creating a readonly view using a readonly

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Readonly views are those views thorough which the data can be selected but no

DML operation is made through the view to the base table.

This type of view is basically meant for reporting purposes.

Example :

CREATE OR REPLACE MYVIEW


WITH READ ONLY;

Creating A View Without Having Base Table Forcible Option

Example :

CREATE OR REPLACE FORCE VIEW MYVIEW

AS SELECT * FROM A;

A= TABLE NOT EXIST

Display a message like bellow

Warning : view is created with compilation error

SYNONYM

Synonyms are nothing but a duplicate name of an existing object. The advantage of a

synonyms name is to provide a short object name. Synonyms name is a schema object it

doesnt hold the data of an object rather than holds the references of an object.

Synonym is basically 2 types

1. Private Synonym

2. Public Synonym

Private synonym is a type of synonym once it is given to an object, it can be

accessed in a specified user , where as public synonym is a type of synonym once it is

given to an object can be accessed in any user.

Syntax to create a public or private synonym

Syntax :

CREATE [PUBLIC] SYNONYM

FOR

Example :

CREATE SYNONYM ME

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FOR MYEMP;

The above example will create a private synonym which is only access in a particular user

where the synonym is created.

To see the names of existing synonyms

Syntax :

SELECT SYNONYM_NAME, TABLE_NAME

FROM USER_SYNONYMS;

PUBLIC SYNONYM

Example :

CREATE PUBLIC SYNONYM ME

FOR MYEMP

**Note : A public synonym can only be created being present in a super user. We can

create a synonym of a existing synonym.

INDEX

It is nothing but a schema object which is required to arrange the records in proper

manner using references.

The advantage of index is to make the query access faster. If no index is created for

a particular column, during data search the total table scan occurs.

In oracle index is categorized in 2 different types :

1. Unique Index / Implicit Index

2. Non-unique / Explicit Index

Unique Index is a type of index which is automatically created by the

oracle Server whenever primary key or unique key constraints are exposed on

particular columns.

Where as Non Unique indexes are those indexes which are explicitly

created by an user on those columns, the columns which have hugely duplicate values.

Syntax :

CREATE INDEX

ON (COL_NAME);

Example :

CREATE INDEX MYEMP_COPMIDX

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ON MYEMP(DEPTNO,ENAME)

Required whenever an user search the data multi condition wise.

To see the output

SELECT * FROM EMP

WHERE DEPTNO=20 AND ENAME= SMITH;

UNIQUE INDEX

Whenever an unique index will be created automatically by the system , the

name of the index will be same as the constraint name given by the user or given by the

system.

**Note : An index file can be deleted in 2 different manners.

1. Explicitly using drop command

2. Implicitly whenever a table is dropped.

SEQUENCE

It is nothing but a schema object required to generate a linear no . It may be in

ascending order or descending .

Syntax :

CREATE SEQUENCE

[INCREMENT BY ]

[START WITH ]

[MAXVALUE N | NO MAXVALUE]

[MINVALUE N | NO MINVALUE]

[CYCLE | NOCYCLE]

[CACHE N | NOCACHE]

Note : Sequence is schema object which is only meant for insert purpose

Example :

CREATE SEQUENCE MYLINE;

The above example will create a sequence whose initial value is 1, each

incremented by 1 and generate infinite values.

Creating A Cyclic Sequence

Example :

CREATE SEQUENCE MYLINE

MAXVALUE 5

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CYCLE

CACHE 3

The above example will create a sequence whose initial value will

be 1 each time incremented by 1 and generate 5 nos and do the same for thrice.

Descending Sequence

Example :


INCREMENT BY -1

MAXVALUE 10

MINVALUE 1

Modification Of Sequence

Example :


MAXVALUE 5;

ALTER SEQUENCE MYLINE

MAXVALUE 10;

ALTER SEQUENCE MYLINE

NOMAXVALUE;

**Note : Any clause of a sequence can be alter except start with clause

DCL

Oracle supports user concept and schema concept to protect the object from invalid

user.

To create and manipulate schema Oracle provides a super user called system

identifier by manager.

To Create A User :

Syntax :

CREATE USER

IDENTIFIED BY

Example :

CREATE USER ORISSA

IDENTIFIED BY BBSR;

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To Delete An Existing User

Syntax :

DROP USER ;

To Delete A Filled User

Syntax :

DROP USER CASCADE;

Example :

DROP USER ORISSA CASCADE;

To Change The Password Of An User

Syntax :

ALTER USER

IDENTIFIED BY

Example :

ALTER USER SCOTT

IDENTIFIED BY LION

To See The Name Of Current User

Syntax :

SHOW USER;

**Note : User creation and deletion can exclusively done from the super user but

to change the password of a user, the user can take the help of super user or by the

user won the password.

To Jump One User To Another

Syntax :

CONNECT /CONN USERNAME ;

ENTER PASSWORD : PASSWORD;

CONNECTED

Example :

CONNECT SCOTT;

ENTER PASSWORD : MANAGER

CONNECTED

**Note : Connect is a SQL * Plus command required to jump from one user to

another without existing out of SQL * Plus.

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To Show All User

Syntax :

SELECT USER_NAME FROM DBA_USERS;

Whenever an user created in oracle database it will never work unless and until

some rules are given to it, those rules are technically known as privileges.

Privileges are 2 types :

1. System Privileges

2. Object Privileges

SYSTEM PRIVILEGE

System privileges are those privileges which are given to individual user ,

what can be done and what cant be .

OBJECT PRIVILEGE

Object privileges are those privileges are given to object, what can be done

and what cant be.

System Privileges are

1. Create Session

2. Create Table

3. Create View

4. Create Synonym

5. Create Sequence

6. Create Index

7. Create Procedure

Object Privileges are

1. Select 2. Insert

3. Update

4. Delete

5. Execute

*Note : Among the above privileges Create Session privileges is the primary privilege

requires to activate n user by creating session Id.

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To impose or revoke the above privileges from an user or from object DCL

provides

1. Grant

2. Revoke

Grant System Privileges To User

Syntax :

GRANT SP1, SP2..,N

TO | ROLE;

Revoke System Privileges From User

Syntax :

REVOKE SP1, SP2..,N

FROM | ROLE;

Grant Object Privileges To User

Syntax :

GRANT OP1, OP2..,N

ON

TO ;

Revoke Object Privileges From User

Syntax :

REVOKE OP1, OP2..,N

ON

FROM ;

**Note : System privileges are those privileges granted or revoked from the super user

only.

Object privileges are granted or revoked by that user who won the user.

WORKING WITH ROLE

Role is nothing but a container, contains system privileges which can be granted to

one user or different users. Role can only created in the system user.

Example :

CONNECT SYSTEM/MANAGER

CREATE ROLE SYSROLE;

GRANT CREATE SESSION, CREATE TABLE, CREATE VIEW

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TO SYSROLE;

GRANT SYSROLE

TO ORISS;

Display Role Names

SELECT ROLE

FROM USER_ROLES;

**Note : The above example is the example of user defined role .Apart from that

Oracle provide some system defined role to activate the user.

1. Resources (Contains All General User Privileges)

2. DBA (Contains All Super User Privileges).

PL SQL

Though PL SQL is pronounced as a language, but it is not a language typically rather

than it is a mechanism ortechnology implemented on Oracle Server to manipulate the

Database programmatically using SQL Commands .

Every Programming Language uses four different Blocks to develop an application

and those are :

1. Declare

2. Input

3. Process

4. Output

In some programming language the above blocks are physically in nature and they

are identified by some keywords. Those types of languages are basically known as Block

Structure Language. Eg: COBOL.

Where as in some programming language the above blocks are logical in nature and

only they follow rule. Those types of languages are Unblock Structure Language. Eg.

C, C++, etc.

PL SQL is an example of Block Structure Language, where the total program is

divided into 3 different Blocks.

1. Declare Optional

2. Begin Mandatory (Program Construct)

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Exception Optional

3. End ; Mandatory

DECLARATION

Declaration block is a block which is responsible for declaration of identifier types,

cursors to be used in PL SQL. This block is identified by declare keyword. This Block is

optional in nature.

BEGIN/END

This block is responsible for input, process and output in Pl SQL programme. Pl

SQl always starts execution from begin and end with end. This is mandatory.

EXCEPTION

This block is meant for error handling in PL SQL. Whenever an error occurs at PL

SQL automatically system control will navigate the exception block and thus the execute

the program normally, identified by the keyword exception. This is optional in nature.

The minimum requirement of a language is an identifier , and identifiers minimum

requirement is data types.

PL SQL provide 2 types of data type :

1. SCALAR DATA TYPE

2. COMPOSITE DATA TYPE

Scalar Data Type is a data type which can store one value at one point of

time in form of one variable.

Composite Data Type is a data type which can store multiple values at one

point of time in form of one variable.

SCALAR DATA TYPE

CHAR, VARCHAR2, NUMBER, DATE, BOOLEAN

Scalar Data Type provides an Attribute %type.

COMPOSITE DATA TYPE

User defined data type or type declaration. It provides an attribute called

%rowtype.

Declaring A Variable

Syntax :

DECLARE

V_NAME DATATYPE(SIZE);

A NUMBER (4);

V_NAME DATATYPE(SIZE):=

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A NUMBER(4):= 10;

Note : In PL SQL assignment operators is := .Each and individual statement in PL

SQL are to be terminated by ;.

To Display Output

DBMS_OUTPUT.PUT_LINE( );

It will work after declaring SET SERVEROUTPUT ON before declaration block.

*Note : To use DBMS_OUTPUT.PUT_LINE( ) a related SQL * PLUS command is

required known as SET SERVER OUTPUT ON, which allows the Server to display the

output in client console. The default behavior is OFF .

SQL Statement To Be Used In PL SQL

Though PL SQL advanced version of SQL, It only uses 3 sublanguages of SQL

1. DQL

2. DML

3. TCL

**Note : DDL & DCL are not allowed in PL SQL.

SELECT Statement in PL SQL

Syntax :

SELECT COL1, COL2, COL3.., N

INTO V1, V2, V3,., N

FROM

WHERE

DBMS_OUTPUT.PUT_LINE(V1)-------------------------------------------

------------------------------------------

DBMS_OUTPUT.PUT_LINE(N)

PL SQL is capable to develop 2 types of programme :

1. Anonymous Block

2. Sub Programme

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Anonymous Block is a type of programme whose programme code is stored inside

client hard diskin form of.SQL file .

Where as Sub Programme is a type of program whose program code is stored

inside Database server in form ofObject.

*Note : The job of anonymous block and sub programme is same to manipulate thedatabase programmatically, but divided into 2 category depending on their security.

To create a new file

Syntax :

Ed

Example :

Ed sysfile

The above example will create a file called sysfile .

Example :

SET SERVER OUTPUT ON

BEGIN

DBMS_OUTPUT.PUT_LINE (HELLO USER)

END;

O/P : HELLO USER

Example :

Write a programme which will display EMPNO, NAME, SAL, JOB of that

employee whose name is Blake.

SET SERVEROUTPUT ON

CLEAR SCREEN

SET VERIFY OFF

DECLARE

VEMPNO NUMBER(4);

VNAME VARCHAR2(20);

VSAL NUMBER(7,2);

VJOB VARCHAR2 (20);

BEGIN

SELECT EMPNO,ENAME, SAL ,JOB

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INTO VEMPNO, VNAME,VSAL, VJOB

FROM EMP

WHERE ENAME= BLAKE;

DBMS_OUTPUT.PUT_LINE ( EMPLOYEE.NO : || VEMPNO)

DBMS_OUTPUT.PUT_LINE ( EMPLOYEE.NAME : || VNAME)

DBMS_OUTPUT.PUT_LINE ( EMPLOYEE.SAL : || VSAL)

DBMS_OUTPUT.PUT_LINE ( EMPLOYEE.JOB : || VJOB)

END;

/

Dynamic Input

Where Ename = &name ;

Working with Scalar Attribute (% Type)

% type is a scalar attribute which is required to declare a variable as a particular

table columns type or another variable type.

The advantage of this attribute is for proper memory management .

Example :

SET SERVEROUTPUT ON

CLEAR SCREEN

SET VERIFY OFF

DECLARE

VEMPNO EMP.EMPNO%TYPE;

A VEMPNO%TYPE

VNAME EMP.ENAME%TYPE;

VSAL EMP.SAL%TYPE ;

VJOB EMP.JOB%TYPE;

BEGIN

SELECT EMPNO,ENAME,SAL,JOB

INTO VEMPNO,VNAME,VSAL,VJOB

FROM EMP WHERE ENAME='BLAKE';

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO : ' || VEMPNO);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO : ' || VNAME);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO : ' || VSAL);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO : ' || VJOB);

END;

/

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In the above exampleVempno is a variable which is employee no type where as A

is variable which is Vempno type

Working With Composite Attribute (%rowtype)

%row type is a composite attribute which is required to declare a variable as a

particular table structure type. The advantage of % row type is it reduces the programme

coding.

Example :

SET SERVEROUTPUT ON

CLEAR SCREEN

SET VERIFY OFF

DECLARE

A EMP %ROWTYPE;

BEGIN

SELECT * INTO A

FROM EMP WHERE ENAME='&NAME';

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO :' || A.EMPNO);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO :' || A.ENAME);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO :' || A.SAL);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO :' || A.JOB);

END;

/

The disadvantage of % row type is , It uses unnecessary memory spaces. To avoid the

above loophole the user can declare its own data type known as TYPE DECLARATION.

Declaring User defined Data type

Syntax :

DECLARE

TYPE IS RECORD

( V_NAME DATATYPE (SIZE),

V_NAME DATATYPE (SIZE),

V_NAME DATATYPE (SIZE),

.N);

V_NAME

Example :

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SET SERVEROUTPUT ON

CLEAR SCREEN

SET VERIFY OFF

DECLARE

TYPE MYTYPE IS RECORD

(VEMPNO EMP.EMPNO%TYPE,

VNAME EMP.ENAME%TYPE,

VSAL EMP.SAL%TYPE,

VJOB EMP. JOB%TYPE);

A MYTYPE;

BEGIN

SELECT EMPNO,ENAME,SAL,JOB

INTO AFROM EMP WHERE ENAME='&NAME';

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO :' || A.VEMPNO);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO :' || A.VNAME);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO :' || A.VSAL);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO :' || A.VJOB);

END;

/

In the above example MYTYPE is a structure where as A is a Variable of Mytype.

WORKING WITH CONTROL STATEMENT

Control statement is a block of executable statement which will perform a specify

task once or no of times unless and until a condition is satisfied.

Those are :

1. IF.ELSE ..ENDIF

2. BASIC LOOP

3. WHILE LOOP

4. FOR LOOP

Syntax of IF :

IF THEN

STATEMENT;

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STATEMENT;

ELSE

STATEMENT;

ENDIF;

Syntax of Nested IF :

IF THEN

STATEMENT;

STATEMENT;

ELSIF THEN

STATEMENT;

STATEMENT;

ELSIF THEN

STATEMENT;STATEMENT;

ELSE

STATEMENT;

END IF;.

OR

IF THEN

STATEMENT;

STATEMENT;

ELSE

IF THEN

STATEMENT;

STATEMENT;

ELSE

IF THEN

STATEMENT;

STATEMENT;

ELSE

ENDIF;

ENDIF;

ENDIF;

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Syntax Of Basic LOOP :

Basic lop is type of looping where the statement is executed

first then it checks the condition . In this type of looping the statement must be executed

once.

Syntax :

LOOP

STATEMENT;

STATEMENT;

STATEMENT;

EXIT [WHEN ];

END LOOP;

Example :

DECLARE

I NUMBER(4):=1;BEGIN

LOOP

DBMS_OUTPUT.PUT_LINE(I);

I:=I+1;

EXIT WHEN I>10;

END LOOP;

END;

/

Syntax Of While LOOP :

This is a type of looping where the condition is checked first

then it will execute the statement. If the condition is set to false the system control will

move to the very next statement after looping.

Syntax :

WHILE LOOP

STATEMENT;

STATEMENT;

------------------;

------------------;

END LOOP;

Example :

SET SERVEROUTPUT ON

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DECLARE

I NUMBER(4):=1;

BEGIN

WHILE I

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and once the execution is done automatically cursor memory will be deleted from the

SERVER.

Cursor is basically categorized in 2 different types

1. Implicit Cursor (Automatically)

2. Explicit (Create By Own)

Cursor ha s4 different stages namely

1. DECLARE

2. OPEN3. FETCH

4. CLOSE

DECLARATION of a cursor means the memory will be declared inside the srver

and the statement will be dumped inside the memory.

OPENING of a cursor means the statement available inside the temporary memory

starts execution and the output returned by the statement will be stored inside the same

memory.

FETCHING of a cursor means the output available inside the temporary memory

will be transport one by one to the respective variable.

CLOSING of a cursor means the memory will be deallocated once the processing

is over.

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IMPLICIT CURSORis a type of cursor where all the above jobs are being dump

implicitly by the system itself but the disadvantages of implicit cursor is it can store one

record at one point of time.

Where as EXPLICIT CURSOR is a type of cursor where all the above jobs are

done by explicitly by the user itself but the advantage of an explicit cursor is it can store

multiple records at one point of time for the processing purpose.

Cursor has four different attributes to manipulate itself.

1. %FOUND

2. %NOTFOUND

3. %ISOPEN

4. %ROWCOUNT

The above attributes are always suffixed with the cursor name either given by the user or

given by the system.

Declaring An Explicit Cursor

Syntax :

DECLARE

CURSOR IS

;

Opening Explicit Cursor

Syntax :

BEGIN

OPEN ;

Fetching An Explicit Cursor

Syntax :

FETCH INTO ;

Closing An Explicit Cursor

Syntax :

CLOSE

END;

/

Simple Cursor Using Basic Loop

Example :

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SET SERVEROUTPUT ON

DECLARE

CURSOR C1 IS

SELECT EMPNO,ENAME,SAL,JOB FROM EMP

WHERE JOB='MANAGER';

A C1%ROWTYPE;

BEGIN

OPEN C1;

LOOP

FETCH C1 INTO A;

EXIT WHEN C1%NOTFOUND;

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NO :'|| A.EMPNO);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE NAME :'|| A.ENAME);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE SALARAY :'|| A.SAL);

DBMS_OUTPUT.PUT_LINE('EMPLOYEE JOB :'|| A.JOB);

DBMS_OUTPUT.PUT_LINE('----------------------');

END LOOP;

CLOSE C1;

END;

/

The above example is an example ofsimple cursor using basic loop.

**Note : Open is a key word which can perform 2 jobs

1. Execute the statement and stores the output inside the same memory

2. Set the pointer to the 1strecord of the record set.

Likewise Fetch is a keyword which can perform 2 jobs

1. Fetch the current record into the variable

2. Skip the pointer to the nest record of the record set.

Simple Cursor Using For LoopThe advantage of cursor for loop over cursor basic loop is , in cursor loop the

cursor is explicitly declared by the user but opening , fetching, closing is done by the

system itself.

In another words, the advantage of cursor for loop is the coding will be less.

Syntax :

DECLARE

CURSOR IS

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;

BEGIN

FOR IN LOOP

STATEMENT;

STATEMENT;

-----------------;

END LOOP;

END;

/

Example :

SET SERVEROUTPUT ON

DECLARE

CURSOR C1 ISSELECT EMPNO,ENAME,SAL,JOB FROM EMP

WHERE JOB='MANAGER';

BEGIN

FOR A IN C1 LOOP






END LOOP;

END;

/

Advance Cursor Or Cursor With Parameter

Advance cursor is otherwise known as dynamic cursor. The advantage of dynamic

cursor is each time. It will ask for the value and depending upon the value the cursor will

be opened.

Declaring Advance Cursor

Syntax :

DECLARE

CURSOR (ARG DATATYPE) IS

SELECT STATEMENT;

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WHERE COL_NAME=ARG;

BEGIN

OPEN (VALUE/EXPRESSION)

Example :

Advance Cursor In For Loop

Syntax :

Example :

SET SERVEROUTPUT ON

DECLARE

CURSOR C1(VJOB VARCHAR2) IS

SELECT EMPNO, ENAME, SAL , JOB FROM EMP

WHERE JOB=VJOB;

BEGIN

FOR A IN C1('&VJOB')LOOP






END LOOP;

END;

/

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SUBPROGRAMS

Subprograms has to be physical existence inside the server inform of object . Subprograms

are otherwise known as NAME BLOCK when any other block otherwise known as

UNAME BLOCK.

The advantages of subprograms, it is more secured than anonymous block.

Subprograms is categorized in 2 different types.

1. STORED PROCEDURE

2. STORED FUNCTION

Creating A Procedure

Syntax :

CREATE [OR REPLACE] PROCEDURE [(ARG DATATYPE)]

IS/AS

IDENTIFIER DECLARATION

TYPE DECLARATION

CURSOR DECLARATION

BEGIN

STATEMENT;

STATEMENT;

;

END

Example :

PACKAGE

Package is nothing but a container which contains related procedure and function to be

used by one user or different users. The advantage of a package is to make the procedure

& function execution faster.

Package has 2 different parts or blocks.

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1. PACKAGE SPECIFICATION

2. PACKAGE BODY

Package Specificationblock is a block where all procedure & functions are to be declared

or specified to be used inside a package where as Package Body is a block where all the

procedure and function are to be designed which are developed in the

Specification block.

**Note : Procedure & Function specified in the specification block may or

may not be designed in the body block but the procedures & functions designed in the

body block have to be specified in the specification block.

Syntax Of Package Specification :

Syntax :

CREATE [OR REPLACE] PACKAGE

IS / AS

PROCEDURE [(ARG DATATYPE)];



-------------------------------------------------------------N;

END ;

/

Syntax Of Package Body :

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