Problem at 'Set ors1=ocom1.execute' while Accessing RT Data from WinCC

Hello everyone

I am accessing the WinCC Run-time data through Connectivity Pack Queries from WinCC Project Run-time database ending in 'R'.

The problem i am encountering is that it halts and stucks for few seconds (8 to 10 seconds) when it reads each tag. The VB6 breakpoints show that it is the line

"Set ors1=com1.Execute" on which it halts for some time and then progresses. Since i have to read 100 tags in a loop, my VB6 application goes on "Not Responding".

Also the timetsamp it returns as a result is not correct. I am reading last 6 minutes data from WinCC Project activated but it always give data of sometime before(an hour or some minutes back).

Now here comes the real strange thing. When

1) I make the new copy of some old backup of the same WinCC Project and change the Runtime Db name accordingly in Connection string,

2) Reset the TLG_F,TLG_S , ALG data from Tag Logging 'Reset Option' in Archive Configuration,

3) Changes TLG_F Settings as

Time period of all segments ------------------- From 1 week(previously) to 2 hrs

Time period of single segment ----------------- From 1 day(previously) to 1 hrs

4) Reactivates this newly copied WinCC project and retreives data with my application with same queries for last 6 mins after 20 to 25 minutes of the project re- activation

Then,
all goes well and now it doesn't stuck on "Set ors1=ocom1.Execute". It also returns the correct timestamp reading 100 tags in less than 5 seconds.

Once the PC is restarted on any other interruption is made, the same problem occurs again and i get stranded.

It must be mentioned here that the above 4 points i use to rectify the situation works only 5 out of 10 times and create trouble at other times also.

I don't know how these 4 points mutually affects the scenario and the problem goes away 50 % of the time with this.

I would be really grateful if someone can suggest the permanent solution and reasoning of whats going on.

I am using following VB 6 code.

Thanks and Regards


Dim tagid As Integer

Dim tagname As String

Dim sPro As String

Dim sDsn As String

Dim sSer As String

Dim sCon As String

Dim sSql As String

Dim conn As Object

Dim sPro1 As String

Dim sDsn1 As String

Dim sCon1 As String

Dim conn1 As Object

Dim ors As Object

Dim ocom As Object

Dim oRs1 As Object

Dim oCom1 As Object

Dim ssql1 As String

Dim sadd, sadd1 As String

Dim m, n, s

Dim ocom2 As Object

Dim scon2 As String

Dim conn2 As Object

Dim ssql2 As String

sPro1 = "Provider=WinCCOLEDBProvider.1;"

sDsn1 = "Catalog=CC_(projectname)_06_12_26_16_25_27R;" ' Timestamp of when copy is made

sSer = "Data Source=(pcname)\WINCC"

sCon1 = sPro1 + sDsn1 + sSer

ReDim dates(130, 6)

ReDim vals(130, 6)

tagid = 1

For k = 0 To 120 ' No of tags i have to read

' 2.1 Make connection

Set conn1 = CreateObject("ADODB.Connection")

conn1.ConnectionString = sCon1

conn1.CursorLocation = 3

conn1.Open

' 2.2 Use command text for query

Set oRs1 = CreateObject("ADODB.Recordset")

Set oCom1 = CreateObject("ADODB.Command")

oCom1.CommandType = 1

Set oCom1.ActiveConnection = conn1

oCom1.CommandText = ssql1

' 2.3 Fill the recordset

oRs1.MoveFirst

m = oRs1.RecordCount

x = 0

i = 0

j = 0

Do While Not oRs1.EOF

x = x + 1

Text1.Text = Text1.Text & Trim(oRs1.Fields(2).Value)

Text1.Text = Text1.Text & " "

Text1.Text = Text1.Text & Trim(oRs1.Fields(1).Value)

Text1.Text = Text1.Text & " "

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