How to block the system not to create sub tasks if the subtasks are already existing

This article explains hHow to block the system not to create sub-tasks if the subtasks are already existed using the Create on Transition app.

Instructions

1. Add a post-function to the intended transition to create a sub-task.
   To add a post-function, navigate to Cogwheel > Issues > Workflows > select the workflow of the project and edit the same.
2. Select Create Sub-task post function as shown below.
   
3. Select the Conditions & Configurations and add %jql_result_count% in Condition 1 and Regular expression pattern value as "0" by marking the Exact field under Conditions section.
   
   By using the %jql_result_count% and Regular expression pattern value as "0" it will check for the JQL query available under the Configuration section.
4. Under the Configuration section in the JQL query add the value as parent = %original_key%
   
   By using the parent = %original_key% in JQL query section