The following code sample uses the SDK to perform a query on a data set. It determines the
minimum raw value over a one-hour time
period.on error resume next
Dim MyServer 'As Historian_SDK.Server
Dim I
Dim J
Dim K
Dim strComment
Dim lngInterval
Dim TagCount
Dim strDataQuality
Dim iDataRecordset
Dim iDataValue
Dim lEndTime, lStartTime, lNumSamples
Dim lNumSeconds, lNumSamplesPerSecond
Dim RawMin
'Instantiate The SDK
Set MyServer = CreateObject("iHistorian_SDK.Server")
'Attempt Connection
If Not MyServer.Connect("DENALI", "administrator","") Then
result = err.description
else
Set iDataRecordset = MyServer.Data.NewRecordset
'Find the number of samples.
'build query
With iDataRecordset
.Criteria.Tagmask = "EIGER.Simulation00001"
.Criteria.StartTime = DateAdd("h",-1,Now)
.Criteria.EndTime = Now
.Criteria.SamplingMode = 4 'RawByTime
.Criteria.Direction = 1 'forward
.Fields.AllFields
'do query
If Not .QueryRecordset Then
result = err.description
End If
'Some Large number so that real samples are less
RawMin = 1000000
For I = 1 To iDataRecordset.Tags.Count
For J = 1 To iDataRecordset.Item(I).Count
Set iDataValue = iDataRecordset.Item(I).Item(J)
' if the value is good data quality
if iDataValue.DataQuality = 1 then
if iDataValue.Value < RawMin then
rawMin = iDataValue.Value
end if
end if
lNumSamples = lNumSamples + 1
Next
Next
End With
End If
Result = RawMin
'Disconnect from server
MyServer.Disconnect
Historian