Types of tables

[Former Member]

Hi all,

we all know that we have three types of tables in abap.

1. Transparent table.

2. Cluster table.

3. Pooled table.

Transparent table exits with same name and same no. of fields at datadictionary level as well as database level.

whether Cluster table and Pooled table exit at databaselevel or dictionary level.

and whether view exits at datadictionary level or database level.

[Former Member]

Hi all,

we all know that we have three types of tables in abap.

1. Transparent table.

2. Cluster table.

3. Pooled table.

Transparent table exits with same name and same no. of fields at datadictionary level as well as database level.

whether Cluster table and Pooled table exit at databaselevel or dictionary level.

and whether view exits at datadictionary level or database level.

[Former Member]

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 at the database level.

It is not necessary to create indexes and technical settings for pooled and cluster tables.

Difference between transparent tables, pooled tables & Cluster Table.-

Transparent tables:

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.

Pooled tables.

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.

Cluster Tables

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.

Views

Contents of a view are dynamically generated when called from a program.

Hope this helps.

Vinodh Balakrishnan

[Former Member]

Pooled table are stored in table pool at the database level.

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.

Regards,

Maha

.

[Former Member]

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.

pooled table.

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.

The definition of a pool consists essentially of two key fields (Tabname and Varkey) and a long argument field (Vardata).

If a pooled table record is saved, it is stored in the table pool assigned. The name of the pooled table is written to the field Tabname. The contents of all key fields of the pooled table are written as a string to field Varkey and the contents of all data fields as a string to field Vardata. The length of the string stored in Vardata is entered in field Dataln by the database interface.

Due to the structure of a table pool, there are certain restrictions on the pooled tables assigned to it. The name of a pooled table may not exceed 10 characters. Since Varkey is a character field, all key fields of a pooled table must have character data types (for example, CHAR, NUMC, CLNT). The total length of all key fields or all data fields of a pooled table must not exceed the length of the Varkey or Vardata field of the assigned pool.

cluster table

Several logical data records from different cluster tables can be stored together in one physical record in a table cluster.

A cluster key consists of a series of freely definable key fields and a field (Pageno) for distinguishing continuation records. A cluster also contains a long field (Vardata) that contains the contents of the data fields of the cluster tables for this key. If the data does not fit into the long field, continuation records are created. Control information on the structure of the data string is still written at the beginning of the Vardata field. A table cluster has the following structure:

The records of all cluster tables with the same key are stored under one key in the assigned table cluster. The values of the key fields are stored in the corresponding key fields of the table cluster. The values of all data fields of the assigned cluster tables are written as a string to the Vardata field of the table cluster. Besides the actual data values, the data string contains information on the structure of the data and which table it comes from. If the string exceeds the maximum length of the Vardata field, a continuation record is written with the same key values. The continuation records for a key are distinguished by their value in field Pageno. The actual length of the string in the Vardata field is stored in the Pagelg field by the database interface.

You need the structural information stored in the ABAP Dictionary to read the data from a pooled table or cluster table correctly. These tables can therefore only be processed using Open SQL with the cluster interface, and not with Native SQL directly in the database.

The data is stored in the table pool or table cluster at the database level.

please reward points if helpful,

shylaja

[Former Member]

Hi Vinay,

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

Regards,

Chandru

[Former Member]

Hi,

I think Cluster table and Pooled table exist at the database level. From the following document I feel like that. Pls check:

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

Views are not stored physically.

Regards,

Renjith Michael.

[Former Member]

HI vinay,

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).

Cluster tables : These are also logical tables which must be assigned to table cluster.

Both these tables will be available in database, but not the same structure as available in data dictionary.

Views are nothing but a structure which is available only in dictionary not in database. The records will be assigned only at the run time.

Reward Points if useful.

Regards,

Sarathy.