Thanks for your response,
As you said, this is exactly what I did. Including a metric field will only return the rows pertaining to that metric, so I then used the includeZeroImpression = true flag, this is what I want all the keywords with their ApprovalStatuses. However, this flag includes duplicate entries (including null) for a given keyword. So, based on the set of fields (id, AdgroupId, CampaignId and ApprovalStatus), one cannot tell which status is the latest, this is where I am struggling, may be I am on the wrong path in achieving this, so a bit of more help is appreciated.
thanks.