Jmeter-While controller is not exiting from loop

Question

I have JDBC request which has modified_date which will populate with value depends on payload size. For small payload it will populate the date and time value immediately, for large size it will take from 10 to 30 minutes. I have added JSSR223 post processor for JDBC request and i am capturing the modified_date and saving in variable "modified". I have added while controller with ${__javaScript(vars.get("Modified"))=="null"} and added same JDBC request with constant timer.

So the while controller keeps looping and it is not stopping or exiting after the value is populated for modified_date. Can you please help.

Answer 1

As per documentation

Variables, functions (and properties) are all case-sensitive.

So Modified and modified are different beasts, you need to mind the case and change the While Controller's condition to ${__javaScript(vars.get("Modified"))=="null"}

Also you don't need any scripting in order to save JDBC Request sampler result into a variable, just define it under "Variable names" section:

and given your query returns a single result you will have it in ${modified_1} JMeter Variable.

More information: Debugging JDBC Sampler Results in JMeter