hi

[Former Member]

What is Cluster and Transparent Table..? How do we create it..?

Can anyone send materials for it.

[Former Member]

http://help.sap.com/saphelp_nw04/helpdata/en/cf/21f0b7446011d189700000e8322d00/frameset.htm

check with this.

Reward points if useful

Madhavi

[Former Member]

Hi

Hope it will help you.

Reward if help.

The following are the table types used in SAP :

Transparent Tables

There is a physical table on the database for each transparent table.

The names of the physical table and the logical table definition in the

ABAP/4 Dictionary agree. All the business and application data is store

in transparent tables.

Pooled table

Pooled tables can be used to store control data (e.g. screen sequences,

program parameters or temporary data). Several pooled tables can be

combined to form a table pool. The table pool corresponds to a physical

table on the database in which all the records of the allocated pooled

tables are stored.

Cluster table

Cluster tables contain continuous text, for example documentation.

Several cluster tables can be combined to form a table cluster. Several

logical lines of different tables are combined to form a physical record

in this table category. This permits object-by-object storage or

object-by-object access. In order to combine tables in clusters, at

least part of the keys must agree. Several cluster tables are stored in

one corresponding table on the database.

I. Transparent tables (BKPF, VBAK, VBAP, KNA1, COEP)

Allows secondary indexes (SE11->Display Table->Indexes)

Can be buffered (SE11->Display Table->technical settings) Heavily updated tables should not be buffered.

II. Pool Tables (match codes, look up tables)

Should be accessed via primary key or

Should be buffered (SE11->Display Table->technical settings)

No secondary indexes

Select * is Ok because all columns retrieved anyway

III. Cluster Tables (BSEG,BSEC)

Should be accessed via primary key - very fast retrieval otherwise very slow

No secondary indexes

Select * is Ok because all columns retrieved anyway. Performing an operation on multiple rows is more efficient than single row operations. Therefore you still want to select into an internal table. If many rows are being selected into the internal table, you might still like to retrieve specific columns to cut down on the memory required.

Statistical SQL functions (SUM, AVG, MIN, MAX, etc) not supported

Can not be buffered

IV. Buffered Tables (includes both Transparent & Pool Tables)

While buffering database tables in program memory (SELECT into internal table) is generally a good idea for performance, it is not always necessary. Some tables are already buffered in memory. These are mostly configuration tables. If a table is already buffered, then a select statement against it is very fast. To determine if a table is buffered, choose the 'technical settings' soft button from the data dictionary display of a table (SE12). Pool tables should all be buffered.

Tables Documentation

https://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/25c1f5d1-0901-0010-d495-e96d02a0...

[Former Member]

Hi,

See:

http://help.sap.com/saphelp_47x200/helpdata/en/81/415d363640933fe10000009b38f839/frameset.htm

Regards,

Renjith Michael.

[Former Member]

hi,

pooled tables:

These are logical tables, which must be assigned to a table pool when they are defined. Pooled tables can be used to store control data (such as screen sequences or program parameters).

http://help.sap.com/saphelp_47x200/helpdata/en/81/415d363640933fe10000009b38f839/frameset.htm

cluster table:

A table cluster combines several logical tables in the ABAP/4 Dictionary. Several logical rows from different cluster tables are brought together in a single physical record. The records from the cluster tables assigned to a cluster are thus stored in a single common table in the database.

http://help.sap.com/saphelp_47x200/helpdata/en/81/415d363640933fe10000009b38f839/frameset.htm

reward if ts useful

Edited by: Rajasekhar Reddy on Jan 22, 2008 12:21 PM