Deleting Data from Calculated points

When creating data in calculated points you may decide to change you sampling period.

How do you go about deleting data from the historian?

I tried the query below in OLEDB/SQLServer.

It seems the iHistorian provider doesn't support deleting.
Am I doing this wrong? Is there another way of deleting data?
I expected to be able to delete data for the most recent 96 hours configured on the archive.



SELECT * FROM OPENQUERY(T155HIST,
'
SELECT timestamp, value , quality
FROM ihRawdata
WHERE
tagname = "SK704.SHIFT_RCC"
and timestamp between "2014-12-16 23:00:00" and "2014-12-26 12:00:00"
AND samplingmode=rawbytime
')
order by timestamp desc


delete FROM OPENQUERY(T155HIST,
'
SELECT timestamp, value , quality
FROM ihRawdata
WHERE
tagname = "SK704.SHIFT_RCC"
and timestamp in ("2014-12-20 15:16:43.0000000", "2014-12-20 15:16:44.0000000" )

')