write optimized, direct , standard dso

[Former Member]

hi,

     plz tell me in which scenario we will use write optimized dso, direct dso, standard dso??? and the exact difference between all of the 

note:don't tell that standard have 3 tables,direct and write op are having 1 table

[former_member214415]

Hi Venkatesh,

Standard DSO- This DSO is used in data flow or you can say for staging purpose. From this DSO you can transfer the data to further targets like info cube or DSO.

This DSO has three tables

1. New data table- data is stored in this table before the activation of DSO.

2. Active table- Once the DSO is activated, Data moves to this table and change Log table parallel.

3. change log table- Change log table is used to maintain the record history or for transferring the delta to the further target.

As this DSO is used in data flow so its better to create SID during activation of this DSO so that there would be no performance issue.

Write optimized DSO- This DSO is mainly used when we have to maintain history of data. because here are two keys: semantic key and technical keys. Based on Technical key(0Request, 0Datapackid, 0Record) each record would be unique.

This DSO has only 1 Table :Active table. There is no need to activate the data like standard DSO.

SID is also generated at reporting time only so data loading performance is improved.

Direct update DSO- In this DSO, Data is written from APD(Analysis process Designer) or API(Application programming interface).

This DSO also has only one table: Active table.

SID is generated at the time of reporting.

Thanks,

Swapna  Jain

[Former Member]

hi venkatesh,

by this time you might have some knowledge  regarding the differences and uses of both standard dso and write optimize dso,

first of all dso is data store object which supports flat structure(two dimensional ).

it has overwrite functionality where as infocube is aggregate functionality .

in sap 3.1 x standard dso is the only one used for reporting and  query designing in transactional ods is not used for reporting i.e write optimize in  sap 7.x.in sap 7.x all the three dso 's are used for reporting.

now comes the differences b/w the standard dso and write optimize dso.

standard dso there is a check box sid activation upon generation which is used for generating the report.

it has key fields,which acts as primary key , and data fields,  it acts upon record number where as in write optimize dso acts on request number (primary key) and it has semantic keys(char) and data fields(keyfigures).

standard dso has three tables

new table ,(from new table data loads to active and change log table)

active data table,(from active data table to target(infocube let say) we use  a schedular full update  as dtp)

and  change log table .(from change log table to data target tables we use  schedular as delta update as dtp).

standard dso is used for generating reports and can be used for multi providers and infosets.

Standard DSO:- -------------- Key fields-> Maxi 16. Data Fields-> 749 * Here we can place char and T char in data fields also, but we can't place KF in Key fields.

in sdso  has Activation Process  Loading is possible  Generate Export data source(Data Mart) is possible-> Delta also enabled.

in write optimize dso Export genarate data source is also possible, Delta is possible the Request no.

in standard dso has 3 tables as mentioned in the above .

but in write optimize dso has only active table .

it used for only historical data.

to use wdso in reporting we have  to pass dso into another dso.

and in write optimize dso doesn't support overwrite functionality instead it appends the data.

it takes less time for query performance since there is no need of activation of sid table upon generation.

and one more thing in change log table contain new image, space , before image , newdata, and record deletion , modification ,,,,,,,,,,,.

this are the basic differences which i know , hope u might have understood it little more ....

[Former Member]

-          Primarily designed for initial staging of source system data. Business rules are only applied when the data is updated to additional Info Providers. Stored in at most granular form.Can be used for faster upload.  Records with the same key are not aggregated ,But inserted as new record, as every record has new technical  key.    Data is available in active version immediately  for further Processing.    There is no change log table and activation queue in it. Data is saved quickly. Data is stored in it at request level, same as in PSA table.  Every record has a new technical key, only inserts. It is Partitioned on request ID (automatic). It allows parallel load, which saves time for data loading. It can be included in Process chain, and we do not need activation step for it. It supports archiving.

[Former Member]

Hi Venkat

The major difference between three types of DSO are..

Type                                   Structure                         Data Supply                              SID Generation

Standard DSO               Consists of three tables:       From data transfer process          Yes

                                     activation queue,

                                      table of active data,

                                      change log

Write-Optimized DSO      Consists of the table of           From data transfer process       No

                                      active data only

DSO for Direct Update    Consists of the table of               From APIs                            No

                                   active data only

[former_member186082]

Hi Venkatesh,

Standard DSO

• Mailny useful for delta management as detail history of record is maintained in Changelog table using 0RECORDMODE.
• SIDs are generated only after activation, hence data is available for reporting after activation only.
• Data records with same key are aggregated
• Reporting possible and data stored in detail level.

WDSO

•   This supports faster data loading compared to Standard DSO. Hence these DSOs are used as staging layers. Further loading will be from these DSOs applying business logics.
• As it has only once table (Active data table ), activation is not required separately. Hence saves time in loading and data availability for data marting / reporting.
• SIDs will be generated after loading. Hence data is available for reporting soon after loading.
• Data records with same key are not aggregated

Direct DSO

• As Venkatesh and Aravind said, this is used for APD analysis and BAPIs are required for loading.
• SIDs cannot be generated.
• Data records with same key are not aggregated in this too

Have a look at this which gives you more details and scenarios where these are used

Hope this clears your doubt regarding DSOs

http://help.sap.com/saphelp_nw04s/helpdata/en/F9/45503C242B4A67E10000000A114084/content.htm

Regards

Chandu

[Former Member]

Hi Chandra,

Write optimized DSO Use in BEx Queries

For performance reasons, SID values are not created for the characteristics that are loaded. The data is still available for BEx queries. However, in comparison to standard DataStore objects, you can expect slightly worse performance because the SID values have to be created during reporting.

If you want to use write-optimized DataStore objects in BEx queries, we recommend that they have a semantic key and that you run a check to ensure that the data is unique. In this case, the write-optimized DataStore object behaves like a standard DataStore object. If the DataStore object does not have these properties, you may experience unexpected results when the data is aggregated in the query.

Regards,

Aravind.

[Former Member]

Hi,

Standard DSO:This type of DSO is mostly used for Detailed level reporting and Detailed level data storage.  It can be used in scenarios of RRI (report to report interface) to refer the detailed level query from and summery query.

Write Optimized DSO: Mainly this type of DSO's are used for faster loading of large amount of data and then forward the delta to other data targets in BW. Mainly used at Data staging layer e.g. in AP, AR and GL scenarios data will be transferred from DSO to further cube.

Direct Update DSO: In these DSO's data loading through DTP's is not possible, and BAPI's are used to update this. Such DSO's are mainly used to store the APD analysis results.

Check these links for scenarios....

http://help.sap.com/saphelp_nw04s/helpdata/en/03/c97842b180c153e10000000a1550b0/frameset.htm

http://help.sap.com/saphelp_nw04s/helpdata/en/b6/de1c42128a5733e10000000a155106/content.htm

http://help.sap.com/saphelp_nw04s/helpdata/en/c0/99663b3e916a78e10000000a11402f/content.htm

Regards,

Aravind.

[Former Member]

Hi

You will get this information if you can able to google it.

Standard DSO: As we all know it has change log table which maintains delta records(changed/New) properly so that we can correctly update the data to further data targets.

Standard DSO is used in most of the data flows where data staging is required before you apply business rules and update it to the target.

Write Optimized DSO: This is used for data backup(Corporate memory) or if you have to handle with large data sets because it does not require data activation.

Direct Update DSO: This DSO has read and write functionality. This will be useful mostly in APD (Analysis Process Designer) or for RDA where you have to write data into tables and read the data to load it to further targets.

Regards,

Venkatesh