difference in type pool and table pool

[Former Member]

hi all,

can anybody tell me that what is difference between type-pool

and table-pool???

regards saurabh.

[Former Member]

Hi,

refer to these links

type-pool

The introductory statement TYPE-POOL can only be used for type groups (type T programs). A program introduced with the TYPE-POOL statement can only contain global type definitions and constants declarations. The CLASS-POOL statement is generated automatically where required by the ABAP Dictionary - you should not insert it into programs manually.

see this link for more info on type-groups:

http://help.sap.com/saphelp_nw70/helpdata/en/fc/eb3138358411d1829f0000e829fbfe/content.htm

table pool

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

rgds,

bharat.

[Former Member]

The following are the table types used in SAP :

I. Transparent tables (BKPF, VBAK, VBAP, KNA1, COEP)

Allows secondary indexes (SE11->Display Table->Indexes)

Can be buffered (SE11->Display Table->technical settings) Heavily updated tables should not be buffered.

II. 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

III. Cluster Tables (BSEG,BSEC)

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

No secondary indexes

Select * is Ok because all columns retrieved anyway. Performing an operation on multiple rows is more efficient than single row operations. Therefore you still want to select into an internal table. If many rows are being selected into the internal table, you might still like to retrieve specific columns to cut down on the memory required.

Statistical SQL functions (SUM, AVG, MIN, MAX, etc) not suppoThe following are the table types used in SAP :

I. Transparent tables (BKPF, VBAK, VBAP, KNA1, COEP)

Allows secondary indexes (SE11->Display Table->Indexes)

Can be buffered (SE11->Display Table->technical settings) Heavily updated tables should not be buffered.

II. 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

III. Cluster Tables (BSEG,BSEC)

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

No secondary indexes

Select * is Ok because all columns retrieved anyway. Performing an operation on multiple rows is more efficient than single row operations. Therefore you still want to select into an internal table. If many rows are being selected into the internal table, you might still like to retrieve specific columns to cut down on the memory required.

Statistical SQL functions (SUM, AVG, MIN, MAX, etc) not supported

Can not be buffered

IV. Buffered Tables (includes both Transparent & Pool Tables)

While buffering database tables in program memory (SELECT into internal table) is generally a good idea for performance, it is not always necessary. Some tables are already buffered in memory. These are mostly configuration tables. If a table is already buffered, then a select statement against it is very fast. To determine if a table is buffered, choose the 'technical settings' soft button from the data dictionary display of a table (SE12). Pool tables should all be buffered.

rted

Can not be buffered

IV. Buffered Tables (includes both Transparent & Pool Tables)

While buffering database tables in program memory (SELECT into internal table) is generally a good idea for performance, it is not always necessary. Some tables are already buffered in memory. These are mostly configuration tables. If a table is already buffered, then a select statement against it is very fast. To determine if a table is buffered, choose the 'technical settings' soft button from the data dictionary display of a table (SE12). Pool tables should all be buffered.

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.

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

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.

[Former Member]

hi about type pool

TYPE-POOLS tp

Type-pools are used to declare a type pool to be used in the program.The specified type pool should already exists in the ABAP DICTONARY(SE11) .Once the type pool has been declared we can use any of the constants and types declared in that type pool.

TYPE-POOL tp

Type-pool statement is used to create a type group in the ABAP dictionary.It is the first statement in the definition.The type group is used to declare constants and types and these must begin with the name of the type pool and underscore.

e.g. TYPE-POOL owntypes.

TYPES num TYPE P DECIMALS 2.

TYPES name(14) TYPE C.

To use these types in the abap program we have to use the statement

TYPE-POOLS .

e.g. TYPE-POOLS owntypes.

DATA customer TYPE owntypes_num.

DATA name TYPE owntypes_name.

[vinod_vemuru2]

Hi,

Type pool is a place where u will declare some constants, types etc. In our programs if we include the type pool statement then we can use all the constants, types declared in the pool. It is similar to TOP Include of the report where we will do the declarations and uses them in form includes and main program.

Table pool is a global area where some set of logically related data base tables are collected and placed in this area.

Thanks,

Vinod.