Oracle 11g has introduced Compound Triggers, before we go deep in to this we need to first understand what is the need for it. Will this help me to resolve any issue which was prominent untill 10g, Let us define the problem first
Allow only new version of the business transaction i.e, allow insert only when there is an change in its attribute and maintain the record history. This has to be done through trigger.With this thought let us proceed. Let us have two attributes ID_COL1,ID_COL2 per business transaction identified by ID, ID_TYPE and Effective Date Time – EFF_DT.
Create the table and Constraints