3698149 - Task chain fails when running the task object "data flow with input parameters" in Datasphere

A data flow with input parameters runs successfully when executed independently. However, when this data flow is incorporated into a task chain, the task chain fails to prompt for the input parameters. After executing the task chain, both the corresponding data flow and the task chain fail. The task chain monitor logs the following error for the data flow: 
Graph failure: producer1 failed with the following error: [90004] Error parsing expression ["###" = ]: no viable alternative at input '<EOF>'.; group=default, message=Graph failure: producer1 failed with the following error: [90004] Error parsing expression ["###" = ]: no viable alternative at input '<EOF>'. 

 (Note: ### denotes the column name utilized with the input parameter.)

"Image/data in this KBA is from SAP internal systems, sample data, or demo systems. Any resemblance to real data is purely coincidental." 

SAP Datasphere

1. Create a data flow.
2. Define input parameters without default values in the data flow.
   
3. Save and deploy the data flow.
4. Add the data flow into the task chain.
5. Run the task chain.
6. In task chain monitor, observe that the task chain and data flow fail.

The data flow with non-default input parameters cannot be executed by the task chain. As per Creating Input Parameters in Task Chains | SAP Help Portal, task chain only supports the following task objects with non-default input parameters:

• SQL script procedures
• transformation flows
• nested task chains

• Use a transformation flow with input parameters instead of the data flow.
• Define a default value for each input parameter in the data flow. 

task chain issue, data builder, failure, schedule, scheduling , KBA , DS-DI-SCH , Scheduling and Task Chains , DS-DI-DF , Data Flows , Problem