I suggest you use a tFlowToIterate in between those components to create a global variable storing the count value produced on tDBInput.
The job will become something like this:
tDBInput --row1--> tFlowToIterate --If--> tMsgBox
Considering the schema on tDBInput has a column called "count", tFlowToIterate will automatically create a global variable called "row1.count" and you can use it on your If trigger like this: