LO Extraction Q&A

1.  What is the difference between LIS and LO?

A:        1. Level of Information, Lo provides Data Sources specific to level of information. For Ex: 2LIS_11_VAHDR – Sales Order Header Information, 2LIS_11_VAITM – Sales Order Item, 2LIS_11_VASCL – Sales Order Scheduler, but in case of LIS it provides information structures specific to Sales Order Information.

            2. Lo uses V3 update (Asynchronous Background Process), which gives the option of executing the LUW’s in the background, but in case of LIS we use V1 or V2.

            3. In Lo, we fill the Setup Tables and once the data is completely extracted into BW side we can delete the Setup Tables Back again by using the T-code LBWG. But in case of LIS we never delete the contents of the information Structure once it is filled, apart from this information structure is also filled with Delta Records, which is of no use.

2.                  What are the steps for generating Lo Data Source?

A:        Since Lo Data Sources are given as part of Business Content in Delivered Version To create a Copy of the same data source in active version, Go to T-Code RSA5, Select the data source and click on ‘transfer datasource’ button, to maintain the ready made extract structure given along with the datasource, go to the T-Code LBWE and click on the ‘Maintenance ‘ link to maintain the Extract Structure by moving the fields from the communication structures, if the required field is not available in the communication structure then we go for enhancing the data source. Since the extract structure is re-generated, we need to generate the data source by clicking the data source link and customize the extract structure by using the following check boxes ‘selection, hide, inversion, field only known in exit’ and then save it. Then choose the delta update mode as Queued Delta among (Direct Delta, Serialized V3 Update, Un serialized v3 update and queued delta) and click on inactivate link to activate the datasource. Then replicate the data source in BW side and start Migrating the data.

3.         How do we migrate the data in LO?

            To be on the safer side, we prefer to delete the Setup Tables by using the T-Code LBWG and specify the application component and also we clear the Delta Queues by using the T-Code SMQ1 and we clear the Extractor queues by using the T-Code LBWQ then lock Related T-Codes, then run the Statistical Setup by using the T-Code OLI*BW, to fill the setup tables then run the initial Loads or Full Loads to extract all the data from Setup Tables into BW side, then once done successfully we go back to R/3 LBWE to setup the periodicity of the V3 job, which could be hourly or two hourly depending on the number of transactions, more the transactions v3 Job  should be scheduled more  frequently and then Finally locks can be released, so that user can start recording the transactions.

  NOTE: These Migrations are always done in the Week Ends after the office hours and T-Codes are usually locked and unlocked by the basis people.

3.                  What are the different Delta Update modes and explain each?

A.                Direct Delta:- In case of Direct delta LUW’s are directly posted to Delta Queue (RSA7) and we extract the LUW’s from Delta Queue to SAP BW by running Delta Loads. If we use Direct Delta it degrades the OLTP system performance because when LUW’s are directly posted to Delta Queue (RSA7) the application is kept waiting until all the enhancement code is executed.

B.                 Queued Delta: - In case of Queued Delta LUW’s are posted to Extractor queue (LBWQ), by scheduling the V3 job we move the documents from Extractor queue (LBWQ) to Delta Queue (RSA7) and we extract the LUW’s from Delta Queue to SAP BW by running Delta Loads. Queued Delta is recommended by SAP it maintain the Extractor Log which us to handle the LUW’s, which are missed.

C.                 Serialized V3 Update: - In case of Serialized V3 update LUW’s are posted to Update Queue (SM13), by scheduling the V3 job which move the documents from Extractor queue (LBWQ) to Delta Queue (RSA7) in a serialized fashion and we extract the LUW’s from Delta Queue to SAP BW by running Delta Loads. Since the LUW’s are moved in a Serial fashion from Update queue to Delta queue if we have any error document it doesn’t lift the subsequent documents and as it sorts the documents based on the creation time, there every possibility for frequent failures in V3 job and missing out the delta records. It also degrades the OLTP system performance as it forms multiple segments with respective to the change in the language.

D.                Un serialized V3 Update: - In case of Un serialized V3 update LUW’s are posted to Update Queue ( SM13 ), by scheduling the V3 job which move the documents from Extractor queue ( LBWQ ) to Delta Queue ( RSA7 ) and we extract the LUW’s from Delta Queue to SAP BW by running Delta Loads. Since the LUW’s are not moved in a Serial fashion from Update queue to Delta queue if we have any error document it considers the subsequent documents and no sorting of documents based on the creation time. It improves the OLTP system performance as it forms a segment for one language.

4.                  How do you enhance a LO Datasource?

A.                The enhancement procedure is same as any other data source enhancement but only difference is that instead of appending the fields to the Extract structure we append the field to the communication structure and move the field from communication structure to extract structure in Maintenance link in T-code LBWE. Deselect the hide check box and field only known in exit check box when generating the data source, then we write the enhancement code to populate the data into the enhanced fields by using the enhancement RSAP0001 this enhancement contains four function exits, that is EXIT_SAPLRSAP_001(for transaction data data source),EXIT_SAPLRSAP_002(For master data attribute)EXIT_SAPLRSAP_003(For master data texts), EXIT_SAPLRSAP_004 (Master data Hierarchies ). We use the internal table C_T_DATA in coding.

5.                  What is the T-code for deleting Set Up tables?

A.                LBWG.

6.                  What is the Importance of Delta Queue?

A.                Delta Queue (RSA7) Maintains 2 images one Delta image and the other Repeat Delta.

            When we run the delta load in BW system it sends the Delta image and when ever            delta loads and we the repeat delta it sends the repeat delta records.

7.                  What does the total column indicate in RSA7 Delta queue?

A.                For each set of LUW either available in both Delta and Repeat Delta or not it counts as one LUW.

8.                   What you mean by LUW?

A.                LUW stands of Logical Unit of Work. When we create o new document it forms New image ‘N’ and when ever there is a change in the existing document it forms before image ‘X’ and after Image ‘ ‘ and these after and before images together constitute one LUW. Before image is always backed up by after image.

9.                  When we are initializing the data source do we need to Lock the posting in SAP R/3?

A.                Yes, that is the reason we normally do this data migration steps during weekends in non-office hours, not to disturb the business.

10.              How do we Re-initialize a LO Data source?

A.          Firstly we lock as transactions as see that we have posting done to Extractor queue (LBWQ) in case of Queued Delta and Update queue (SM13) in case of Serialized V3 Update and Un serialized V3 update, Then if we don’t want the delta records in SM13 and LBWQ we can delete them or if we want them into SAP BW, then we schedule the V3 job and collect LUW’s into Delta Queue and Extract the LUW’s from Delta Queue to SAP BW by running Delta Loads in SAP BW. Once the Queues are Cleaned up, delete the Setup Tables by using the T-Code LBWG and specify the application component, then run the Statistical Setup by using the T-Code OLI*BW, to fill the setup tables then run the initial Loads or Full Loads to extract all the data from Setup Tables into BW side, then once done successfully we go back to R/3 LBWE to setup the periodicity of the V3 job, which could be hourly or two hourly depending on the number of transactions, more the transactions v3 Job should be scheduled more  frequently and then Finally locks can be released, so that user can start recording the transactions.

            NOTE: These Migrations are always done in the Week Ends after the office hours and     T-Codes are usually locked and unlocked by the basis people.