Hi Kathakali,
If you apply change in structure ods/cube for example add ZABC object.
1) Your ZABC object is found in your datasource?, if yes then only need del data for ods/cube, add your new object and mapping, active your objects and transport to QA and reload since psa for your test.
2) If your object ZABC not found
2.1) Your datasource is standar: you need create a enhacement in your structure and datasource for add ZABC, and you need write your code in cmod trx.
2.2. Your datasource is generic: you need add in your structure, program or view and datasource ZABC object.
3) You need know if your ds is delta or not.
3.1 If is delta and your ds is standar: You need realize a inicialization since ECC side and executing four infopackage initialization in your BW side. afther you only need execute delta loads. (This process must be long time and depend of your records in ECC).
3.2 If is delta and your ds is generic. You only need execute inicialization in BW side.
3.3 If your ds is full, you no have problems for load, you can load for periods for reload your data.
In all cases you need know many records, which is what you need?, what is your scenario?, your datasource?, need more information about your process.
I hope help you.