tables

[Former Member]

give examples of pool tables, cluster table and tranparent tables?

[Former Member]

Hi,

There are three categories of database tables in the ABAP Dictionary.

Transparent Table:

A physical table definition in the database for the table definition which is stored in the ABAP Dictionary for transparent tables when the

table is activated. The table definition is translated from the ABAP

Dictionary to a definition of the particular database.

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 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.

See the documetation at:

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

http://help.sap.com/saphelp_nw04/helpdata/en/81/415d363640933fe10000009b38f839/frameset.htm

A transparent table in the dictionary has one to one relationship with a table in the database.

For each transparent table in the data dictionary there is one associated table in the database.The database table has the same name, the same number of fields and fields have same names as the transparent table definition. Transparent tables are used to hold application data. Application data is master data or transaction data used by an application.

e.g. master data - table of customers

Transaction data - order placed by the customers.

Pooled table in R/3 has a many to one relationship with a table in the database. For one table in the database there are many tables in the R/3 data dictionary.R/3 uses pooled tables to hold large number of very small tables. You might create a table pool if yoou need to create hundreds of small tables that each hold only a few rows of data.

A cluster table is similar to pool table . It has many to one relationship with the table in the database.

They are used to hold the data from a few(approximatelly 2 to 10) very large tables. They would be used when these tables have a part of their primary keys in common and if data in these tables are all accessed simultaneously.A cluster is advantageous in the case where data is accessed from multiple tables simultaneously and those tables have at least one of their primary key fields in common.Cluster table reduce number of database reads and thereby improves performance.

[Former Member]

<h1>Cluster tables.</h1>

BSEG - Accounting Document Segment

PCDCLS - Cluster structure for change documents

RFBLG - Cluster for accounting document

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.

A cluster table have many to 1 relationship. Cluster table are much more complex and you cannot display the data of a cluster table directly. Cluster table have be read and display via your ABAP program.

Table cluster is a special table type in ABAP dictionary. The data from different tables can be stored in a table cluster.

A table cluster should be used exclusively for storing internal control information (screen sequences, program parameters, temporary data, continuous text such as documentation).

Check this link for creating cluster tables.

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

<h1>Pooled tables</h1>

doesnt maintain any primary key relationship

these are more no of pooled table which had less no of

records

Pooled tables are buffered

Example : Pool table : MDTC

<h1>TRANSPARENT TABLES</h1>

transparent table in the dictionary has one to one relationship with a table in the database.

For each transparent table in the data dictionary there is one associated table in the database.The database table has the same name, the same number of fields and fields have same names as the transparent table definition. Transparent tables are used to hold application data. Application data is master data or transaction data used by an application.

e.g. master data - table of customers

Transaction data - order placed by the customers.

Transpernt table is table which is being crated in the database. This table will store atcual data.

Example MARA, VBAK..

Regards

Chandru

[Former Member]

Hi,

pls follow the links,

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

http://www.sap-img.com/abap/the-different-types-of-sap-tables.htm

they have more clear explanatiion..

pls reward if helps,

regards.

[Former Member]

Hi,

Cluster Table: BSEG

Transparent Table: KNA1, LFA1, VBAK, VBAP

Pooled table: A017

check the below link for better understanding the difference between cluster and pooled tables.

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