04-10-2006 6:39 PM
Hi friends,
Could anyone Please Let me know the difference between Transparent , Cluster and Pool Tables?
Please Let me know.
Thank in advance.
Thanks&Regards.
Tina
04-10-2006 6:43 PM
Hi Tina,
<b>Transparent Table</b>:
Exists with the same structure both in dictionary as well as in database exactly with the same data and fields.
<b>Pooled Table</b>:
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.
<b>Cluster Table</b>:
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 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.
Hope this will help.
Regards,
Ferry Lianto
04-10-2006 6:46 PM
04-10-2006 6:46 PM
<b>A transparent table</b> 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.Transparent tables in the dictionary has a one-to-one relation with the table in database. Its structure corresponds to single database field. Table in the database has the same name as in the dictionary. Transparent table holds application data
<b>A clustered and a pooled table</b> 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.Pooled tables in the dictionary has a many-to-one relation with the table in database. Table in the database has the different name as in the dictionary. Pooled table are stored in table pool at the database level.
http://www.datamanagementgroup.com/Resources/Articles/Article_0106_2.asp
Thanks
Sudheer
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.
04-10-2006 6:52 PM
HI TINA
u can check with this too
Transparent table:
Tables can be defined independently of the database in the ABAP Dictionary. The fields of the table are defined together with their (database-independent) data types and lengths.
A table definition in the ABAP Dictionary has the following components:
Table fields: The field names and the data types of the fields contained in the table are defined here.
Foreign keys: The foreign keys define the relationships between this table and other tables.
Technical settings: The technical settings define how the table is created on the database.
Indexes: Indexes can be defined for the table to speed up data selection from the table.
There are three categories of database tables in the ABAP Dictionary.
A physical table definition is created in the database for the table definition 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.
On the other hand, pooled tables and cluster tables are not created in the database. The data of these tables is stored in the corresponding table pool or table cluster. It is not necessary to create indexes and technical settings for pooled and cluster 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 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.
more info
http://help.sap.com/saphelp_erp2004/helpdata/en/81/415d363640933fe10000009b38f839/frameset.htm
http://cma.zdnet.com/book/abap/ch03/ch03.htm
Check this links.
http://help.sap.com/saphelp_40b/helpdata/en/4f/991f82446d11d189700000e8322d00/applet.htm
http://www.techinterviews.com/?p=198
Regds,
naveen
04-10-2006 6:53 PM
HI Tina,
<b>i)Transparent tables</b> - Exists with the same structure both in dictionary as well as in database exactly with the same data and fields. Both Opensql and Nativesql can be used.
<b>ii)Pool tables & Cluster tables</b> - These are logical tables that are arranged as records of transparent tables. one cannot use native sql on these
tables (only open sql).They are not managable directly using database system tools.
<b>Pooled table:</b>
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.
<b>Cluster table</b>
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 part of the keys must agree. Several cluster tables are stored in one corresponding table on the database.
Please find these links which will help u to understand more.
http://help.sap.com/saphelp_nw04/helpdata/en/cf/21f0d1446011d189700000e8322d00/content.htm
Hope this will help you.
Cheers
Sunny
reward points ,if found helpful