Answer / subhajit guha

View in sql called the virtual table.Physically it has no
existance, so that it don't occupy the space.It retrives
the data from original table at runtime.
Views are stored in ORACLE system catalog.
Basically, in realtime environment views are used to
protect the main table for operation.Besides for security
purpose view must be used.i.e. one user can hide the main
tale from other user for creating view.

On basic of creation of view, it is divied into two pars....

1. Simple view: In that case columns for same table(single
table) are fetched for creating a view.

Syntax: SQL>create view <view_name> as select <column
name1.column name2....> from table where <condition>;

2. Complex view: Columns are fetched from different tables
on basis of operation would perform.Generally for join
operation it is used.

Syntax: SQL>create view <view_name> as select <col1..coln
from table 1>,<col 1..col n for table 2>....< .. for table
n> from table 1,..,table n where <condition>;

On basis of operations on view ... it is divided inti two
parts:

1. Read only view, 2. Updatable view
** incase of updatable view insertion,deletion and updation
can be done...... aggregation,rowid,rownum and any group
function cann't be performed.
** incase of read only view, only view canbe read, no DML
operations cann't be perfomed.

to drop a view ..... we use:

SQL>drop view <view_name>;

Answer / manoj

This is a virtual table do not have physical existence
only at run time it retrive valves from one or more than
one tables.

opertion: insert , update , delete

case 1:- If view created on only one table than DML
can perform on that TABLE

case 2:- If view Made on more than one then DML cant
possiple

Answer / satyanarayana reddy

It is an object in the database.
Which doesn't store any data.
Which is stored as a select statement in the datadictionary
tables.

Answer / parna

It is an object in the database.It doesn't store any data.
It is stored as a select statement in the datadictionary
tables.This is a virtual table which do not have physical
existance only at runtime.It retrive values from one
table,if it is created only one table than DML can perform
on that table.
Operations are used in view:-Insert,Delete,Update.

Answer / agrawalamit166

This is a virtual table do not have physical existence
only at run time it retrive valves from one or more than
one tables.

opertion: insert , update , delete

case 1:- If view created on only one table than DML
can perform on that TABLE

case 2:- If view Made on more than one then DML is
possible only when all not null values will be included in
the query. means we can insert values in multiple tables
with the help of view if we take all not null field at the
time view creation.

Answer / jyoti ranjan samal

View is called vertual table which provides access to a sub
set of column when one or more table.
2.View can derived data one or more table.
3.It is a Query stored as an object of the database which
does not have own data.

Answer / ashis

View is a virtual table or logical table or it can be
represented as mirror if table.View allows performing
transaction on table virtually.Table may contain "n" number
of views.View can be based on single table or more than one
table with help of join.

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