Using GetDCIValue function

[Nagav]

Hi , I am trying to do transformation scripting using GetDCIValue function
like
dciName = "ISTRTTS2";
dciId = FindDCIByDescription($node, dciName);
dciObj = GetDCIObject($node, dciId);
tableOld = GetDCIValue($node, dciId);
followed by
for (j = 0; j < tableOld->rowCount; j++)

The script work fine for first time, every time when I restart netxms server and agent, I am get error 14 at line " for (j = 0; j < tableOld->rowCount; j++)"

As a work around, if I remove the transformation script allow the DCI to collect data and add script, the script will work.
It seems script expects the last data, but when we restart the netxms server and agent, why it is not picking data from database
How can I handle this problem? Any suggestion

[tomaskir]

When server first starts, the DCI has no new collected data yet.

Script around it and return an error like so:

tableOld = GetDCIValue($node, dciId);
if (tableOld == null) return 0;

[Nagav]

Thank you very much.. it works now