Examples for Pooled and Cluster tables

[Former Member]

Hi all,

Can any body please say me the difference between Pooled and cluster tables, and Please give me the examples for both

Thanks in Advance

[Former Member]

Hi,

Pool table

A database table defined in the ABAP Dictionary whose database instance is assigned to more than one table defined in the ABAP Dictionary. Multiple pool tables are assigned to a table pool in the database. The key fields of a pool table have to be character-type fields. The table pool's primary key consists of two fields: TABNAME for the name of a pool table, and VARKEY for the interdependent contents of the key fields in the corresponding pool table. The non-key fields of the pool table are stored in compressed format in their own column, called VARDATA, of the table pool. The only way to access pool tables is by using Open SQL. Joins are not allowed.

Table Pool

Database table in the database that contains the data of several pool tables.

Cluster Table

Database table defined in the ABAP Dictionary, whose version on the database is not only assigned to one table defined in the ABAP Dictionary. Several cluster tables are assigned to a table cluster in the database. The intersection of the key fields of the cluster tables forms the primary key of the table cluster. The other columns of the cluster tables are stored in compressed form in a single column VARDATA of the table cluster. You can access cluster tables only via Open SQL, and only without using joins.

Table Cluster

Database table in the database that contains the data of several cluster tables.

Note: Never mix up with a database table that has the necessary structure for storing data clusters in database tables and in the shared memory. Those are called INDX-type, with reference to the database table INDX supplied by SAP. Data clusters are groupings of data objects for transient and persistent storage in a selectable storage medium. A data cluster can be processed using the statements IMPORT, EXPORT, and DELETE FROM.

1) T040, T040A--pooled

2) BSEG, BSES---->cluster

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.

A001

A004

A005

A006

A007

A009

A010

A012

A015

A016

A017

A018

A019

A021

A022

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 type. This permits object-by-object storage or object-by-object access. In order to combine tables in clusters, at least parts of the keys must agree. Several cluster tables are stored in one corresponding table on the database.

AUAA

AUAB

AUAO

AUAS

AUAT

AUAV

AUAW

AUAY

BSEC

BSED

BSEG

BSES

BSET

CDPOS

you can refer to the link http://help.sap.com/saphelp_nw04/helpdata/en/cf/21f083446011d189700000e8322d00/content.htm for standard documentation.

reward points if it is helpful..

regards,

Omkar.

Message was edited by:

Omkaram Yanamala

Message was edited by:

Omkaram Yanamala

[Former Member]

Thanks for your quick response,

As per my knowledge, pooled tables can hold large no of small tables where as cluster tables can hold small no fo large tables.

In case of custer tables the screen information is stored like screen no etc. But I dont know that what sort of large tables cluster table holds.

Please correct me if iam wrong.

waiting for yor relpy

[Former Member]

Cluster can hold a large n° of records, this is right.

Check the F1 help on "cluster" word in SE11 for BSEG, for eg.

Erwan

[Former Member]

Check BSEG & BKPF table one is cluster othe ris transparent.

Go to SE11 and press F1 on "cluster", u 'll get more explanation.

Hope this helps,

Erwan

[S0025444845]

hi,

a017 and a018 are example of pooled table.

regards,

sudha

[Former Member]

Hi,

Pool table

A database table defined in the ABAP Dictionary whose database instance is assigned to more than one table defined in the ABAP Dictionary. Multiple pool tables are assigned to a table pool in the database. The key fields of a pool table have to be character-type fields. The table pool's primary key consists of two fields: TABNAME for the name of a pool table, and VARKEY for the interdependent contents of the key fields in the corresponding pool table. The non-key fields of the pool table are stored in compressed format in their own column, called VARDATA, of the table pool. The only way to access pool tables is by using Open SQL. Joins are not allowed.

Table Pool

Database table in the database that contains the data of several pool tables.

Cluster Table

Database table defined in the ABAP Dictionary, whose version on the database is not only assigned to one table defined in the ABAP Dictionary. Several cluster tables are assigned to a table cluster in the database. The intersection of the key fields of the cluster tables forms the primary key of the table cluster. The other columns of the cluster tables are stored in compressed form in a single column VARDATA of the table cluster. You can access cluster tables only via Open SQL, and only without using joins.

Table Cluster

Database table in the database that contains the data of several cluster tables.

Note: Never mix up with a database table that has the necessary structure for storing data clusters in database tables and in the shared memory. Those are called INDX-type, with reference to the database table INDX supplied by SAP. Data clusters are groupings of data objects for transient and persistent storage in a selectable storage medium. A data cluster can be processed using the statements IMPORT, EXPORT, and DELETE FROM

This link also helps you...

http://help.sap.com/saphelp_nw04/helpdata/en/cf/21f083446011d189700000e8322d00/content.htm

Check out these threads

EXAMPLES

http://help.sap.com/saphelp_nw04/helpdata/en/cf/21f083446011d189700000e8322d00/content.htm

Regards,

Priyanka.

[Former Member]

Hi

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

Cluster Tables (BSEG,BSEC, KONP )

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

No secondary indexes

see the link

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

<b>

Reward points for useful Answers</b>

Regards

Anji

[S0025444845]

Hi,

Transparent Table : Exists with the same structure both in dictionary as well as in database exactly with the same data and fields.

Pooled Table : Pooled tables are logical tables that must be assigned to a table pool when they are defined. Pooled tables are used to store control data. Several pooled tables can be cominied in a table pool. The data of these pooled tables are then sorted in a common table in the database.

Cluster Table : Cluster tables are logical tables that must be assigned to a table cluster when they are defined. Cluster tables can be used to strore control data. They can also be used to store temporary data or texts, such as documentation.

The below link is to .... how to create the cluster & pooled table

http://help.sap.com/saphelp_46c/helpdata/en/81/415d363640933fe10000009b38f839/frameset.htm

bseg is cluster table and a017 and a018 are pooled table.

regards,

sudha