View, Clustur & Pooled Table
Hi,
I have few questions on the above topics.
How can we retreive data from View , Clustur & Pooled Table using Select statements.
If possible can you explain me with an example.
what kind of data can we retreive from them . for example BSEC - how can we use it .
Thank you in advance.
Ry
hi,
You can access them using SELECT statements, you CAN NOT use joins though.
For example, BSEG is a cluster table.
report znave_0003 .
data: ibseg type table of bseg with header line.
parameters: p_bukrs type bseg-bukrs.
select * into table ibseg from bseg
up to 100 rows
where bukrs = p_bukrs.
loop at ibseg.
write:/ ibseg-bukrs, ibseg-belnr.
endloop.
to retrieve the data from a view....
Declare the internal table with the type of View.
Data : itab type table of zview001.
or write select query as
select * from zview001 into corresponding fields of itab.
Also you can uncheck the Unicode checks active (checkbox) in the program attributes.
{When you check that unicode checkbox, you should use an internal table without a header line. Instead you should declare a work area)
Hope it helps...
~~Guduri
Similar Messages
-
Is it possible to use a pooled table when creating a view?
Hi,
I am trying to create a view based on table A005 but this table is a Pooled table and the system wont allow me to create a view on it.
Is there any way to do this?
Thanks,Hi,
Join stmt can not be executed on Cluster tables & pooled tables.
regards,
ajit. -
How to extract data from a pool table?
Hello,
I want to create an generic extractor for table T030, but this is a pool/cluster table and it is not possible to create a view for such a table.
Do somebody know how to solve this problem? Does there exist function modules to read the data from a pool data?
Thanks
TheodorFunction Module would be your best bet..considering thats the best way as far as performance is taken into consideration.
But there is a work around too...
If the other table u use in the join is not a clusture table then u can create a view on that table and u can add append structure to this with fields from the clusture table and use an exit to populate it.
Try it Will Work...used this technique when I used KONV.* This Procedure does not decrease performance considerably.
at least in my case as thre were only a few fields i needed from pool table
Hope this Helps
Anand Raj -
Alternative for Pooled table M_VMVAC in ECC 5 version
Hi,
Pooled table M_VMVAC in version 3.1i does not exist
in ECC 5.Can anyone tell me the alternative for this?
Pool/cluster is M_VMVA in 3.1i version
Helpful answers will be rewarded
Thanks
KiranCheck data base view V_VMVAC.
Regards
Sridhar -
when we will use cluster table , pooled table and transparent tables...
FOr Tables
http://www.erpgenie.com/abap/tables.htm
For Tables
<b>Pooled Tables, Table Pools, Cluster Tables, and Table Clusters</b>
These types of tables are not transparent in the sense that they are not legible or manageable directly using the underlying database system tools. They are managed from within the R/3 environment from the ABAP dictionary and also at runtime when they are loaded into application memory.Pool and cluster tables are logical tables. Physically, these logical tables are arranged as records of transparent tables. The pool and cluster tables are grouped together in other tables, which are of the transparent type. The tables that group together pool tables are known as table pools, or just pools; similarly, table clusters, or just
clusters, are the tables which group cluster tables.Not all operations that can be performed over transparent tables can be executed over pool or cluster tables.
For instance, you can manage these tables using Open SQL calls from ABAP, but not Native SQL.These tables are meant to be buffered and loaded in memory, because they are commonly used for storing internal control information and other types of data with no external (business) relevance. SAP recommends that tables of pool or cluster type be used exclusively for control information such as
program parameters, documentation, and so on. Transaction and application data should be stored in transparent tables.
<b>Table Pools</b>
From the point of view of the underlying DBMS as from the point of view of the ABAP dictionary, a table pool is a transparent table containing a group of pooled tables which, when created, were assigned to this table pool.
Field Type Description
TABNAME CHAR(10) Table name
VARKEY CHAR(n) Maximum key length n =< 110
DATALN INT2(5) Length of the VARDATA record returned
VARDATA RAW(m) Maximum length of the data varies according to DBMS
<b>Table Clusters</b>
Similarly to pooled tables, cluster tables are logical tables which, when created, are assigned to a table cluster. Therefore, a table cluster, or just cluster, groups together several tables of type clusters.Several logical rows from different cluster tables are brought together in a single physical record. The records
from the cluster tables assigned to a cluster are thus stored in a single common table in the database.A cluster contains a transparent cluster key which must be located at the start of the key of all logical cluster tables to be included in the cluster. As well, a cluster contains a long field (VARDATA), which contains the
data of the cluster tables for this key. If the data does not fit into a field, continuation records are created.
Field Type Description
CLKEY1 CHAR(*) First key fields
CLKEY2 CHAR(*) Second key field
CLKEYN CHAR(*) nth key field
PAGENO INT2(5) Number of the next page
TIMESTMP CHAR(14) Time stamp
PAGELG INT2(5) Length of the VARDATA record returned
VARDATA RAW(*) Maximum length of the data section; varies according to database system
<b>Working with Tables</b>
The dictionary includes many functions for working with tables. There are five basic operations you can perform on tables: display, create, delete, modify, copy. Please do not confuse displaying a table with displaying the table entries (table contents). In order to display a table, it must previously exist; otherwise the system will display an error message in the status bar. For the following example, the table TABNA is used. To display this table, from the main dictionary screen, enter the table name in the Object name
input field with the radio button selected next to Tables. Then, click on the Display button at the bottom of the screen, or press the F7 function key, or, alternatively,
select Dictionary object Display from the menu.
In this screen, you can see table information such as
¨ Table type, shown next to the name of the object. In the example, it is a transparent table.
¨ Short text description.
¨ Name of the user who made the last change, and the date of the change.
¨ Master language.
¨ Table status. On the screen, you can see this table is saved and active.
¨ Development class. For information on development classes, refer to Chap. 6.
Delivery class, which sets the maintenance group for the table. It controls how tables will behave during client copy procedures, upgrades, and so forth.¨
Tab. Maint. Allowed flag, which indicates whether you can generate a screen for maintaining table entries.
¨Then, on the lower part of the screen, you can see the table fields with all associated characteristics such as:
¨ Field name.
¨ Key indicator. When set, this field is the primary key, or part of it.
¨ Data element.
¨ Basic data type.
¨ Length.
¨ Check table.
¨ Short text, describing the field.
Additional information about the table can be displayed by selecting the corresponding functions from the menu or directly from the application toolbar, such as keys, indexes, or technical settings.
Regards,
Balaji
**Rewards for helpful answers -
I make a join with a pool table the compiler writes
Für Pool-Tabellen, Cluster-Tabellen und Projektions-Views ist JOIN
for pool-Tables, Cluster-Tables and Projections-View is no JOIN allowed.
What can I do to read the data from the table a005 in join.
thanks.
Waseem>
Ahmad Waseem wrote:
> What can I do to read the data from the table a005 in join.
> thanks.
> Waseem
Hello Waseem,
Ans is DONOT use JOIN. You have to use FOR ALL ENTRIES.
You can JOIN only transperant tables. This is where JOIN scores over FOR ALL ENTRIES
BR,
Suhas -
How to create a datasource from a pool table ?
Hi guys,
Is there anyone who faced the same problem.
I need to create an datasource from the table TIV5T to get texts in BW .
This table is a pool table . When i want to create the DS in RSO2 i got the message :
Only transparent tables and database views can be extracted
I try to create a projection vue, or use the standard vue : same error.
Any Idea ??
Thank you .
DinahHi DInah,
Please go through the following threads.
Re: How to extract data from a pool table?
Datasource on Pool Table
Regards,
Ravikanth -
Pooled table and clustred table
pooled table and clustred table
Hi
Pooled Tables, Table Pools, Cluster Tables, and Table Clusters
These types of tables are not transparent in the sense that they are not legible or manageable directly using the underlying database system tools. They are managed from within the R/3 environment from the ABAP dictionary and also at runtime when they are loaded into application memory.Pool and cluster tables are logical tables. Physically, these logical tables are arranged as records of transparent tables. The pool and cluster tables are grouped together in other tables, which are of the transparent type. The tables that group together pool tables are known as table pools, or just pools; similarly, table clusters, or just
clusters, are the tables which group cluster tables.Not all operations that can be performed over transparent tables can be executed over pool or cluster tables.
For instance, you can manage these tables using Open SQL calls from ABAP, but not Native SQL.These tables are meant to be buffered and loaded in memory, because they are commonly used for storing internal control information and other types of data with no external (business) relevance. SAP recommends that tables of pool or cluster type be used exclusively for control information such as
program parameters, documentation, and so on. Transaction and application data should be stored in transparent tables.
Table Pools
From the point of view of the underlying DBMS as from the point of view of the ABAP dictionary, a table pool is a transparent table containing a group of pooled tables which, when created, were assigned to this table pool.
Field Type Description
TABNAME CHAR(10) Table name
VARKEY CHAR(n) Maximum key length n =< 110
DATALN INT2(5) Length of the VARDATA record returned
VARDATA RAW(m) Maximum length of the data varies according to DBMS
Table Clusters
Similarly to pooled tables, cluster tables are logical tables which, when created, are assigned to a table cluster. Therefore, a table cluster, or just cluster, groups together several tables of type clusters.Several logical rows from different cluster tables are brought together in a single physical record. The records
from the cluster tables assigned to a cluster are thus stored in a single common table in the database.A cluster contains a transparent cluster key which must be located at the start of the key of all logical cluster tables to be included in the cluster. As well, a cluster contains a long field (VARDATA), which contains the
data of the cluster tables for this key. If the data does not fit into a field, continuation records are created.
Field Type Description
CLKEY1 CHAR(*) First key fields
CLKEY2 CHAR(*) Second key field
CLKEYN CHAR(*) nth key field
PAGENO INT2(5) Number of the next page
TIMESTMP CHAR(14) Time stamp
PAGELG INT2(5) Length of the VARDATA record returned
VARDATA RAW(*) Maximum length of the data section; varies according to database system
Working with Tables
The dictionary includes many functions for working with tables. There are five basic operations you can perform on tables: display, create, delete, modify, copy. Please do not confuse displaying a table with displaying the table entries (table contents). In order to display a table, it must previously exist; otherwise the system will display an error message in the status bar. For the following example, the table TABNA is used. To display this table, from the main dictionary screen, enter the table name in the Object name
input field with the radio button selected next to Tables. Then, click on the Display button at the bottom of the screen, or press the F7 function key, or, alternatively,
select Dictionary object Display from the menu.
In this screen, you can see table information such as
¨ Table type, shown next to the name of the object. In the example, it is a transparent table.
¨ Short text description.
¨ Name of the user who made the last change, and the date of the change.
¨ Master language.
¨ Table status. On the screen, you can see this table is saved and active.
¨ Development class. For information on development classes, refer to Chap. 6.
Delivery class, which sets the maintenance group for the table. It controls how tables will behave during client copy procedures, upgrades, and so forth.¨
Tab. Maint. Allowed flag, which indicates whether you can generate a screen for maintaining table entries.
¨Then, on the lower part of the screen, you can see the table fields with all associated characteristics such as:
¨ Field name.
¨ Key indicator. When set, this field is the primary key, or part of it.
¨ Data element.
¨ Basic data type.
¨ Length.
¨ Check table.
¨ Short text, describing the field.
Additional information about the table can be displayed by selecting the corresponding functions from the menu or directly from the application toolbar, such as keys, indexes, or technical settings
Standard table:
The key access to a standard table uses a sequential search. The time required for an access is linearly dependent on the number of entries in the internal table.
You should usually access a standard table with index operations.
Sorted table:
The table is always stored internally sorted by its key. Key access to a sorted table can therefore use a binary search. If the key is not unique, the entry with the lowest index is accessed. The time required for an access is logarithmically dependent on the number of entries in the internal table.
Index accesses to sorted tables are also allowed. You should usually access a sorted table using its key.
Hash table:
The table is internally managed with a hash procedure. All the entries must have a unique key. The time required for a key access is constant, that is it does not depend on the number of entries in the internal table.
You cannot access a hash table with an index. Accesses must use generic key operations (SORT, LOOP, etc.).
Index table:
The table can be a standard table or a sorted table.
Index access is allowed to such an index table. Index tables can be used to define the type of generic parameters of a FORM (subroutine) or a function module.
Just have a look at these links:
http://help.sap.com/saphelp_nw04/helpdata/en/90/8d7304b1af11d194f600a0c929b3c3/frameset.htm
http://help.sap.com/saphelp_nw04/helpdata/en/74/83015785d811d295a800a0c929b3c3/frameset.htm
For creating cluster tables first u have to create table pool ...
create a table and specify the fields and other tecnical settings and
then Goto EXTRAS --> Change Table Category and selct the Pooled table and activate it...
Then Create another table And specify the required fileds and also the settings and then
Goto EXTRAS --> Change Table Category and selct the Cluaster table and in Delivery and
Maintainence Properties mention the Pooled table that u created and activate it...
Regards
Sreeni -
Hi all,
What is the difference of Cluster and pooled tables.and the specific applications.do we get the need to create the pooled tables in implmentations.
u.khan.Hai
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.
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:
Field
Data type
Meaning
CLKEY1
First key field
CLKEY2
Second key field
CLKEYn
nth key field
Pageno
INT2(5)
Number of the continuation record
Timestamp
CHAR(14)
Time stamps
Pagelg
INT2(5)
Length of the string in Vardata
Vardata
RAW (n)
Contains the entries from the data fields of the assigned cluster tables as a string, max. length n depends on the database system used
Cluster Tables
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.
the major 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 the following Link
http://help.sap.com/saphelp_nw04/helpdata/en/cf/21f083446011d189700000e8322d00/content.htm
Thanks & regards
Sreenivasulu P -
Joining of cluster and pooled tables ,transparent tables
Hi,
I wanted to do join between cluster ,pooled and transparent tables but inner join won't allow to join between transparent or cluster tables or pooled tables . The requirements are that join should take place dynamically between transparent ,cluster ,pooled tables .I have written the Function module for joining multiple tables for transparent tables but unable to implement same for the transparent and cluster or pooled tables.How to handle the joining of tables between pooled or cluster and transparent tables kindly provide me the answer .
Thanks,
jahnavi.Hi Jahnavi,
My suggestion would be... if you want to retrieve the data between cluster tables and transparent tables.. its better to go for views instead of cluster tables then that would be easier for you to retrieve the data
let us take one example BSEG its a cluster table where as there is one view VBSEGK it contains almost all the important fields needed so that u can make use of those or you can look into BSIK and BSAK tables so it better to avoid the cluster tables while retriving the data from the performance point of view -
Data Maintenance For Pooled Table
Hi,
I have to make table maintenance for pooled table T052S , Can I make table maintenace , if I have access key, is it feaseable, as I have some requirement , which is to be done. or is there any other method by which user can maintain this table except through SPRO.
thanks
bobbyWe're on ECC 5.0 here and this table already has a maintenance transaction defined - OBB9.
This is how SAP sets up maintenance for a lot of the config tables:
Define a Maintenance View - e.g. V_T052S
Define a Maintenance Dialog
Define a transaction variant on SM30
A user can be given maintenance access for only OBB9 -
hi guru
which type of data is store in cluster table and pooled table?
what is relation between cluster and pooled tableHi,
. 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.
"Major difference betwen Standard tables,Pooled tables and Cluster Tables?
1.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.
2.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.
3.A clustered and a pooled table cannot be read from outside SAP because certain data are clustered and pooled in one field.
4.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.
5.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.
6.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.
7.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.
8.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.
9.A structure is a table without data. It is only filled by program logic at the moment it is needed starting from tables.
10.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.
'The table which store information about Structures and Tables are as follows:
DD02L - table properties
DD02T - table texts
DD03L - field properties
DD03T - field texts
Creating cluster/pool tables:
http://help.sap.com/saphelp_nw04/helpdata/en/cf/21f0b7446011d189700000e8322d00/content.htm
creating transparent tables
http://help.sap.com/saphelp_nw04/helpdata/en/cf/21eb6e446011d189700000e8322d00/frameset.htm
Thanks,
Reward If Helpful. -
What is better to use - Views or Database Tables
Hi,
<b>VIEWS</b>
There are 4 types.
Database View (SE11)
Database views are implement an inner join, that is, only records of the primary table (selected via the join operation) for which the corresponding records of the secondary tables also exist are fetched. Inconsistencies between primary and secondary table could, therefore, lead to a reduced selection set.
In database views, the join conditions can be formulated using equality relationships between any base fields. In the other types of view, they must be taken from existing foreign keys. That is, tables can only be collected in a maintenance or help view if they are linked to one another via foreign keys.
- Help View ( SE54)
Help views are used to output additional information when the online help system is called.
When the F4 button is pressed for a screen field, a check is first made on whether a matchcode is defined for this field. If this is not the case, the help view is displayed in which the check table of the field is the primary table. Thus, for each table no more than one help view can be created, that is, a table can only be primary table in at most one help view.
- Projection View
Projection views are used to suppress or mask certain fields in a table (projection), thus minimizing the number of interfaces. This means that only the data that is actually required is exchanged when the database is accessed.
A projection view can draw upon only one table. Selection conditions cannot be specified for projection views.
- Maintenance View ( SE54 )
Maintenance views enable a business-oriented approach to looking at data, while at the same time, making it possible to maintain the data involved. Data from several tables can be summarized in a maintenance view and maintained collectively via this view. That is, the data is entered via the view and then distributed to the underlying tables by the system.
Please have a look at below link. It will help you.
http://help.sap.com/saphelp_nw04/helpdata/en/cf/21ed06446011d189700000e8322d00/frameset.htm
for more detailed info look on:
http://www.sap-img.com/abap/what-is-the-different-types-and-usage-of-views.htm
https://www.sdn.sap.com/irj/sdn/wiki?path=/display/home/abap+dictionary&
<b>TABLES</b>
Pool Tables
1) Many to One Relationship.
2) Table in the Dictionary has the different name, different number of fields, and the fields have the different name as in the R3 Table definition.
3) It can hold only pooled tables.
cluster Tables:
1) These are logical tables that are arranged as records of transparent tables.
2) One cannot use Native SQL on these tables (only Open SQL).
3) They are not manageable directly using database system tools.
These two table are used to store system data and onother for configural data.
if u want to fetch the data from DB table u need to go for trasperent tables only.
Bcoz transperent tables are one - one relation.
Refer to this link
http://help.sap.com/saphelp_nw04/helpdata/en/81/415d363640933fe10000009b38f839/frameset.htm
INTERNAL TABLES
There are 3 types of Internal tables.
Standard Internal Tables:
Standard tables have a linear index. You can access them using either the index or the key. If you use the key, the response time is in linear relationship to the number of table entries. The key of a standard table is always non-unique, and you may not include any specification for the uniqueness in the table definition.
This table type is particularly appropriate if you want to address individual table entries using the index. This is the quickest way to access table entries. To fill a standard table, append lines using the (APPEND) statement. You should read, modify and delete lines by referring to the index (INDEX option with the relevant ABAP command). The response time for accessing a standard table is in linear relation to the number of table entries. If you need to use key access, standard tables are appropriate if you can fill and process the table in separate steps. For example, you can fill a standard table by appending records and then sort it. If you then use key access with the binary search option (BINARY), the response time is in logarithmic relation to the number of table entries.
Sorted Internal Tables:
Sorted tables are always saved correctly sorted by key. They also have a linear key, and, like standard tables, you can access them using either the table index or the key. When you use the key, the response time is in logarithmic relationship to the number of table entries, since the system uses a binary search. The key of a sorted table can be either unique, or non-unique, and you must specify either UNIQUE or NON-UNIQUE in the table definition. Standard tables and sorted tables both belong to the generic group index tables.
This table type is particularly suitable if you want the table to be sorted while you are still adding entries to it. You fill the table using the (INSERT) statement, according to the sort sequence defined in the table key. Table entries that do not fit are recognised before they are inserted. The response time for access using the key is in logarithmic relation to the number of table entries, since the system automatically uses a binary search. Sorted tables are appropriate for partially sequential processing in a LOOP, as long as the WHERE condition contains the beginning of the table key.
Hashed Internal Tables:
Hashes tables have no internal linear index. You can only access hashed tables by specifying the key. The response time is constant, regardless of the number of table entries, since the search uses a hash algorithm. The key of a hashed table must be unique, and you must specify UNIQUE in the table definition.
This table type is particularly suitable if you want mainly to use key access for table entries. You cannot access hashed tables using the index. When you use key access, the response time remains constant, regardless of the number of table entries. As with database tables, the key of a hashed table is always unique. Hashed tables are therefore a useful way of constructing and
using internal tables that are similar to database tables.
Regards,
Priyanka. -
About pool table??
what for pooled and cluster table used and how to create it???
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.
"Major difference betwen Standard tables,Pooled tables and Cluster Tables?
1.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.
2.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.
3.A clustered and a pooled table cannot be read from outside SAP because certain data are clustered and pooled in one field.
4.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.
5.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.
6.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.
7.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.
8.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.
9.A structure is a table without data. It is only filled by program logic at the moment it is needed starting from tables.
10.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.
'The table which store information about Structures and Tables are as follows:
DD02L - table properties
DD02T - table texts
DD03L - field properties
DD03T - field texts
Creating Pooled Tables/Cluster Tables Locate the document in its SAP Library structure
Procedure
1. In the initial screen of the ABAP Dictionary select object type Table, enter a table name and choose This graphic is explained in the accompanying text Create.
The field maintenance screen for the table is displayed. Table type Transparent table is set as default.
2. Make the necessary entries in the Short description and Delivery class fields on the Attributes tab page. Then define the fields of the table.
Proceed as when Structure link creating a transparent table. Save your entries.
3. Choose Extras
® Change table category.
A dialog box appears in which you have to select the table type Pooled table or Cluster table.
4. Choose This graphic is explained in the accompanying textSelect.
You return to the field maintenance screen for the table. Field Pool/cluster name is displayed on the Attributes tab page in addition to the standard fields.
5. Enter the name of the
table pool or table cluster to which you want to assign the pooled table or cluster table in field Pool/cluster name
Note that the total key length of a pooled table may not exceed the key length of the associated table pool. The key of a cluster table must correspond to the key of the associated table cluster.
6. Proceed as when creating a transparent table (see
Structure link Creating Tables). Remember that you cannot create indexes for pooled or cluster tables.
Note
All the attributes of the Structure link technical settings can be maintained for pooled tables and cluster tables. Before you can access these attributes, however, you must convert the table to a transparent table.
Leaving content frame
creating pool/cluster tables
regards,
srinivas
*reward for useful answers*</b> -
Wat is the exact differences between clustered table and pooled table
hi,
can you tell me ravi...wat is the exact differences between clustered table and pooled table
with regards//
anilreddygHi Anil Reddy
Pooled Tables, Table Pools, Cluster Tables, and Table Clusters
These types of tables are not transparent in the sense that they are not legible or manageable directly using the underlying database system tools. They are managed from within the R/3 environment from the ABAP dictionary and also at runtime when they are loaded into application memory.Pool and cluster tables are logical tables. Physically, these logical tables are arranged as records of transparent tables. The pool and cluster tables are grouped together in other tables, which are of the transparent type. The tables that group together pool tables are known as table pools, or just pools; similarly, table clusters, or just
clusters, are the tables which group cluster tables.Not all operations that can be performed over transparent tables can be executed over pool or cluster tables.
For instance, you can manage these tables using Open SQL calls from ABAP, but not Native SQL.These tables are meant to be buffered and loaded in memory, because they are commonly used for storing internal control information and other types of data with no external (business) relevance. SAP recommends that tables of pool or cluster type be used exclusively for control information such as
program parameters, documentation, and so on. Transaction and application data should be stored in transparent tables.
Table Pools
From the point of view of the underlying DBMS as from the point of view of the ABAP dictionary, a table pool is a transparent table containing a group of pooled tables which, when created, were assigned to this table pool.
Field Type Description
TABNAME CHAR(10) Table name
VARKEY CHAR(n) Maximum key length n =< 110
DATALN INT2(5) Length of the VARDATA record returned
VARDATA RAW(m) Maximum length of the data varies according to DBMS
Table Clusters
Similarly to pooled tables, cluster tables are logical tables which, when created, are assigned to a table cluster. Therefore, a table cluster, or just cluster, groups together several tables of type clusters.Several logical rows from different cluster tables are brought together in a single physical record. The records
from the cluster tables assigned to a cluster are thus stored in a single common table in the database.A cluster contains a transparent cluster key which must be located at the start of the key of all logical cluster tables to be included in the cluster. As well, a cluster contains a long field (VARDATA), which contains the
data of the cluster tables for this key. If the data does not fit into a field, continuation records are created.
Field Type Description
CLKEY1 CHAR(*) First key fields
CLKEY2 CHAR(*) Second key field
CLKEYN CHAR(*) nth key field
PAGENO INT2(5) Number of the next page
TIMESTMP CHAR(14) Time stamp
PAGELG INT2(5) Length of the VARDATA record returned
VARDATA RAW(*) Maximum length of the data section; varies according to database system
Working with Tables
The dictionary includes many functions for working with tables. There are five basic operations you can perform on tables: display, create, delete, modify, copy. Please do not confuse displaying a table with displaying the table entries (table contents). In order to display a table, it must previously exist; otherwise the system will display an error message in the status bar. For the following example, the table TABNA is used. To display this table, from the main dictionary screen, enter the table name in the Object name
input field with the radio button selected next to Tables. Then, click on the Display button at the bottom of the screen, or press the F7 function key, or, alternatively,
select Dictionary object Display from the menu.
In this screen, you can see table information such as
¨ Table type, shown next to the name of the object. In the example, it is a transparent table.
¨ Short text description.
¨ Name of the user who made the last change, and the date of the change.
¨ Master language.
¨ Table status. On the screen, you can see this table is saved and active.
¨ Development class. For information on development classes, refer to Chap. 6.
Delivery class, which sets the maintenance group for the table. It controls how tables will behave during client copy procedures, upgrades, and so forth.¨
Tab. Maint. Allowed flag, which indicates whether you can generate a screen for maintaining table entries.
¨Then, on the lower part of the screen, you can see the table fields with all associated characteristics such as:
¨ Field name.
¨ Key indicator. When set, this field is the primary key, or part of it.
¨ Data element.
¨ Basic data type.
¨ Length.
¨ Check table.
¨ Short text, describing the field.
Additional information about the table can be displayed by selecting the corresponding functions from the menu or directly from the application toolbar, such as keys, indexes, or technical settings
Standard table:
The key access to a standard table uses a sequential search. The time required for an access is linearly dependent on the number of entries in the internal table.
You should usually access a standard table with index operations.
Sorted table:
The table is always stored internally sorted by its key. Key access to a sorted table can therefore use a binary search. If the key is not unique, the entry with the lowest index is accessed. The time required for an access is logarithmically dependent on the number of entries in the internal table.
Index accesses to sorted tables are also allowed. You should usually access a sorted table using its key.
Hash table:
The table is internally managed with a hash procedure. All the entries must have a unique key. The time required for a key access is constant, that is it does not depend on the number of entries in the internal table.
You cannot access a hash table with an index. Accesses must use generic key operations (SORT, LOOP, etc.).
Index table:
The table can be a standard table or a sorted table.
Index access is allowed to such an index table. Index tables can be used to define the type of generic parameters of a FORM (subroutine) or a function module.
Just have a look at these links:
http://help.sap.com/saphelp_nw04/helpdata/en/90/8d7304b1af11d194f600a0c929b3c3/frameset.htm
http://help.sap.com/saphelp_nw04/helpdata/en/74/83015785d811d295a800a0c929b3c3/frameset.htm
Regards
Sreeni
Maybe you are looking for
-
I have updated to version 11 of itunes and now it wont open comes up with comment saying it is not installed correctly or corrupt. Help
-
How do I create a DVD from an iMovie '08 Project?
How do I create a DVD from an iMovie '08 Project? I followed the directions in the help section but when I open iDVD, my project is "grayed out" and I cannot open it in iDVD. Rich Rector
-
my computer had a problem -so the technition had to fix it. and now i don't have itunes on the PC. so i havedownloaded itunes- but when i connected the iphone to the computer i got this massage that says that it's not the same virsion as on my iphone
-
If I change the rotation property of a panel, the title will disappear. Although I use the embed font file. How should I do ? <mx:Panel title="Title" width="300" height="500" id="panel" click="panel.rotation+=2;"/> CSS FILE @font-face{ src: url("msyh
-
What is the best program for converting text PDF documents to audio files?
Hi all, I'm looking for a program (cost is not a factor, I'm looking for the highest functionality) that will convert PDF files (text, often scanned documents) to audio files, preferably ones that are able to have the recordings saved.