topic Diff b/w VIEW and CLUSTER TABLE in Application Development and Automation Discussions

Diff b/w VIEW and CLUSTER TABLE

Former Member — Fri, 08 Feb 2008 08:03:51 GMT

Hi Guys,

Can anybody let me know the difference between cluster table and view?

I know about diff types of view, just i need difference?

Regards,

Chandru

Re: Diff b/w VIEW and CLUSTER TABLE

Former Member — Fri, 08 Feb 2008 08:07:52 GMT

hi,

A database view is defined in the ABAP Dictionary and automatically created on the database during

activation. Accesses to a database view are passed directly to the database from the database interface.

The database software performs the data selection.

If the definition of a database view is changed in the ABAP Dictionary, the view created on the database

must be adjusted to this change. Since a view does not contain any data, this adjustment is made by

deleting the old view definition and creating the view again in the ABAP Dictionary with its new definition.

The maintenance status defines whether you can only read with the view or whether you can also write

with it. If a database view was defined with more than one table, this view must be read only.

The data read with a database view can be buffered. View data is buffered analogously to tables. The

technical settings of a database view control whether the view data may be buffered and how this should

be done. The same settings (buffering types) can be used here as for table buffering. The buffered view

data is invalidated when the data in one of the base tables of the view changes.

Database views implement an inner join. You only get those records which have an entry in all the tables

included in the view.

Maintenance views implement an outer join.

Hope this is helpful, Do reward.

Re: Diff b/w VIEW and CLUSTER TABLE

Former Member — Fri, 08 Feb 2008 08:18:19 GMT

Hi,

Cluster tables are nothing but Data base tables so my explanation is as follows for ur question.

The Table has a physical storage of data whereas views do not have physical storage of data.

The view is derived from one or more tables which is created only with the required fields

from the database table(s). It can also be created with table inner joins and specifying conditions

for data retrieval.

Regards.

Re: Diff b/w VIEW and CLUSTER TABLE

Former Member — Fri, 08 Feb 2008 08:25:25 GMT

Hi,

Views:

A View is a logical view on one or more tables.

A view on one or more tables i.e., the data from a view is not actually physically stored instead being derived from one or more tables.

A View can be used to summarize data which is distributed among several tables.

Types of Views:

Projection View - It is a view that just retrives some fields from a single table.

Help View - This view is used for Search Help.

Database View - This is a inner join view of one or more tables.

Maintenance View - Helps in creating maintaining data of the application object. The data can be distributed among several tables.

CLUSTER TABLE

Cluster tables where those tables designed for this other restriction you heard from (more than 255 fields). But they have other advantages too. They store information's belonging together in the same database blocks, this improves also performance when you read them

Hope this is helpful, Do reward.

Cheers,

Chaitanya.