Multiple query on the same BC and SetAdminMode

Hello,

My requirement is I need to query first line item under SR,then I need to check on the same BC ,that whether the fetched record is parent record or not,so I’ll query again on the same BC putting the row Id in the parent seq number field ,if any  record is there having this record as parent ID record then nothing,otherwise I need to populate the message against this saying it is not parent one.then I need to move for another record ,need to search again that is it the parent record for any other record & so on.