Oracle Applications Adapter

Hi I am working for first time on Oracle Apps adapter.Here I have a header table, line table and buffer table and whenever data is inserted into line and header tables key information(unique which identifies header and line table data) is inserted into buffer table.Now my task is to retrieve the data from tables.I am thinking of using Query adapter service for that and using SQL trees.But I want to extract one key at a time and it should be picked one and only once and the volume is changing.Can anyone help me in this regard?

I’m intressted too for you subject.
please if someone know a solution…