Transparent,pooled and cluster table

[Former Member]

my friend can any one tell what is transparent table,pooled and cluster table in database. I went through documents there i could not understand what it trys to tell.Please explain the concept of it

[vinod_vemuru2]

Hi Venkatesh,

Transparent table: One to one relation

One table in data dictionary equal to one table in data base.

i. e When u create one transparent tabel in ABAP dictionary one table will be created in Database(Typically Oracle, U can have others also) with same name(Both tabel and fields).

Basically used to hold application data.

EG: EKKO,VBAK etc.

Pooles tabel: Many to one relationship

Many tables in ABAP dictionary equal to one table pool in database. Basically used to hold system data and customization data. One table pool contains large number of pooled tables having data of around 100 records each.

Cluster tables: Many to one relationship

Many tables in ABAP dictionary equal to one table cluster in database. Basically used to hold application data. One table cluster contains few number of cluster tables having data of around large quantities.(In lakhs)

eg:CDPOS, BSEG etc.

Incase of pooled and cluster tables ABAP data dictionary table name and Data base table and field names differs unlike same in case transparent table.

There are some limitations on cluster tables like we can't use joins on these tables, Select on cluster table is always very slow.

When ever we write query on any cluster table in the table cluster data will be fetced for all the table as data for all the tables in the cluster stores as a single record.

In reality we hardly create pooled and cluster tables.

Hope it is clear.

Thanks,

Vinod.

Edited by: Vinod Reddy Vemuru on Jun 28, 2008 7:08 PM

[former_member181995]

Venketesh,

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.

difference between Standard tables, Pooled tables and Clusterd Tables

A transparent table is a table that stores data directly. You can read these tables directly on the database from outside SAP with for instance an SQL statement.

Transparent table is a one to one relation table i.e. when you create one transparent table then exactly same table will create in data base and if is basically used to store transaction data.

A clustered and a pooled table cannot be read from outside SAP because certain data are clustered and pooled in one field.

One of the possible reasons is for instance that their content can be variable in length and build up. Database manipulations in Abap are limited as well.

But pool and cluster table is a many to one relationship table. This means many pool table store in a database table which is know as table pool.

All the pool table stored table in table pool does not need to have any foreign key relationship but in the case of cluster table it is must. And pool and cluster table is basically use to store application data.

Table pool can contain 10 to 1000 small pool table which has 10 to 100 records. But cluster table can contain very big but few (1 to 10) cluster table.

For pool and cluster table you can create secondary index and you can use select distinct, group for pool and cluster table. You can use native SQL statement for pool and cluster table.

A structure is a table without data. It is only filled by program logic at the moment it is needed starting from tables.

A view is a way of looking at the contents of tables. It only contains the combination of the tables at the basis and the way the data needs to be represented. You actually call directly upon the underlying tables.

Go through this link

http://web.mit.edu/sapr3/dev/sap_table_types.htm

Rewards if helpfull

Regards

Amit.

[former_member598013]

Hi Venkatesh,

Please check out the below link regarding the concept of tables in SAP.

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

&**********Reward Points if helpful**********&

[bpawanchand]

HI

Table pools (pools) and table clusters (clusters) are special table types in the ABAP Dictionary. The data from several different tables can be stored together in a table pool or table cluster. Tables assigned to a table pool or table cluster are referred to as pooled tables or cluster tables.

A table pool or table cluster should be used exclusively for storing internal control information (screen sequences, program parameters, temporary data, continuous texts such as documentation). Data of commercial relevance is usually stored in transparent tables.

Table Pools

A table in the database in which all records from the pooled tables assigned to the table pool are stored corresponds to a table pool.

for more information follow this link

http://help.sap.com/saphelp_46c/helpdata/en/cf/21f083446011d189700000e8322d00/content.htm

next you go through this link

http://help.sap.com/saphelp_46c/helpdata/en/cf/21eb13446011d189700000e8322d00/content.htm

regards

Pavan

[Clemenss]

pool tables to play billiards, cluster tables where there a whole bunch of them and transparent tables you can look through and see your feet

...couldn't resist,

Clemens

[Former Member]

Hi,

Transparent :

Contain a single table. Used to store master data

It has a one-to-one relationship with a table in the database

For each transparent table there is one associated table in the database

The database table has the same name, same number of fields and the fields have the same names

There is only a single table

Single table can have one or more primary key

Secondary indexes can be created

They can be accessed using open and native SQL

USE: They are used to hold master data e.g. Table vendors or table of customers. Example of transaction data is orders placed by customers

Pooled:

They are used to hold a large number of very small tables(stores customizing data or system data)

It has a many-to-one relationship with a table in the database

It is stored with other pooled tables in a single table called table pool in the database

The database table has different name, different number of fields and fields have different names

Table pools contain more tables than table clusters

Primary key of each table does not begin with same fields or fields

Secondary indexes cannot be created

They can be accessed using open SQL only

USE: They reduce the amount of database resources needed when many small tables have to be opened at the same time

Cluster:

They are used to hold data from a few number of large tables.(stores system data)

It has a many-to-one relationship with table in the database

Many cluster tables are stored in a single table in the database called a table cluster

The database table has different name, different number of fields and fields have different names

Contains less tables than table pools

Primary key of each table begins with same fields or fields

Secondary indexes cannot be created

They can be accessed using open SQL only

USE: They would be used when the tables have primary key in common and data in these tables are all accesses simultaneously

[former_member650568]

Hi Friend,

Transparent table: 1 to 1 Relation

1).suppose we are create one table in DDIC, that Same copy will be store in database is called Transpoarent table.

2.) There possible to create secondary index also.

3) Append fields also.

Ex: Trasparent Tables:VBAK - Sales Document: Header Data

VBAP - Sales Document: Item Data

EKKO - Purchasing Document Header

EKPB - "Material Provided" Item in Purchasing Document

T024 - Purchasing Groups

Pooles tabel: 1 to n Relations.

Many small Pool table are combined to form a single table is call Table pool. like (Ex: KAPOL)

2.) There NOT possible to create secondary index also.

3) NOT possibel to Append the fields also.

EX:Cluste Tables: A007 - Division/Customer

A004 - Tax Classification

A006 - Price List Type/Currency/Material

A018 - Material Info Record ..etc.

EX:Table pool:KAPOL

Incase we are create pooled and cluster tables ABAP data dictionary table structure will be different...click below example.

table-pool.png

Cluster tables: Many to one relationship

Many small Cluster table are combined to form a single table is call Table Cluster. like (Ex: RFBLG)

2.) There NOT possible to create secondary index also.

3) Possibel to Append the fields also.

EX:BSEC - One-Time Account Data Document Segment

BSED - Bill of Exchange Fields Document Segment

BSEG - Accounting Document Segment ..etc

Table Cluster: RFBLG

Incase we are create pooled and cluster tables ABAP data dictionary table structure will be different...click below example.

cluster.png

It is not possible to joins condition.

Data fetching from Cluster tables will be slow beacuse it have many small table combinded.

if want any dought then go and check wehter it is joins possible are not go to T-COde - SQVI check with those.

Hope it is clear.