Generic Deltas vs. LO Deltas

Question

Dear All,
I am learner of SAP BI/BW I have one query mentioned below
1)     I would like to know the difference between Generic Deltas vs. LO Deltas u2013 when we used to prefer both the Deltas.
2)     When did you go for Function module and let me know the real time scenario which you faced.
Regards,
Divyesh

Answer 1

Hi..
1) I would like to know the difference between Generic Deltas vs. LO Deltas u2013 when we used to prefer both the Deltas.
Generaic datasource is something which you create when the standard ones doesn't fulfill your requirement.....
To make it delta enable you should select some delta specific field.......which will work as a timestamp.......which will record the changes based on which the new or changed records (delta records) will get fetched......
You have to do the init......and then you can execute the delta.......
Here you are directly fetching data from some Application table, view, Infoset........
Or if the logic is complex..........means you have fetch data from multiple table you can go for a Function Module......
Now...LO deltas are different........here Set up table is mandatory..........because it cannot access data directly from the Application table......
First, you have to fill the set up table..........then run the init.........once the init is done..........after that changes will automatically get recorded in the Delta queue........but here also once catch is there........
Different Update modes are there...........if it is a Queued delta or Unserialized V3 update ..........then the changes and new records will get stored in the Extraction Queue(LBWQ) and Update table (SM13) respectively............then you have to schedule the Collective run in LBWQ to pull the records in RSA7..............only in case of Direct delta changes will directly get recorded in RSA7........
2) When did you go for Function module and let me know the real time scenario which you faced.
if the logic is complex..........means you have fetch data from multiple table you can go for a Function Module......
For an example..........for FI logic is quite complicated.........business specific.......if you just create a view it will not fulfill the requirement.........you will have some business specific logic..........
So in this case you have to go for a FM......
Regards,
Debjani....