Hi

Advantages of views:

1. View the data without storing the data into the object.

2. Restict the view of a table i.e. can hide some of columns in the tables.

3. Join two or more tables and show it as one object to user.

4. Restict the access of a table so that nobody can insert the rows into the table.

Disadvatages:

1. Can not use DML operations on this.

2. When table is dropped view becomes inactive.. it depends on the table objects.

3. It is an object so it occupies space.

Pls. add if I miss any of them.

Thanks

Mohan

hi

Just to add ..Views don't consume space as they are created dynamically ...ex- when you do select * from view_name ;

The inline view is a construct in Oracle SQL where you can place a query in the SQL FROM clause just as if the query was a table name.

select
fs.tablespace_name Tablespace
(df.totalspace - fs.freespace) Used MB
fs.freespace Free MB
df.totalspace Total MB
round(100 * (fs.freespace / df.totalspace)) Pct. Free
from
(select
tablespace_name
round(sum(bytes) / 1048576) TotalSpace
from
dba_data_files
group by
tablespace_name
) df
(select
tablespace_name
round(sum(bytes) / 1048576) FreeSpace
from
dba_free_space
group by
tablespace_name
) fs
where
df.tablespace_name fs.tablespace_name;

advantages

1. hiding the data.

2. you can use two tables data in view.

3. security will be there.

disadvantages

1.when table is not there view will not work.

2. dml is not possible if that is more than one table.

3. it is also database object so it will occupy the space.

hello sir

plz clear that. is view has storage space. if not then y u written this

it is also database object so it will occupy the space.