ServiceNow connector

I hope I am in the right place. I have a Get Task Activity inside a ServiceNow Application Scope. The connection works fine and I am able to retrieve records based on the query specified / generated using the tool. The issue is that the where clause in the query needs to be changed dynamically as being executed based on external factors which become known and change during the process meaning I know what it needs to change to but I am confused as to how to base the where clause on a variable ie: where number=var_name with var_name being the variable. Can this be done? (edited)