Our application is a near realtime dashboard. We have data coming from two processes (A & B) that we need to integrate (java jobs). Those processes are not "talking" to each other but their data needs to end up in one dashboard. Each job writes text files with datetime stamps appended.
I am trying to figure out an approach that will avoid file locks. We dont have a "database" to handle locks for us. Are there any commands in Qlikview to handle locks and tell jobs to wait...for example wait until a qvd has finished being written?
If I use one document (qvw), and it is called by A to load/integrate A's data and then B calls the same document to integrate B's data, i would think we could get bad results even if process A does not lock the qvw while loading (if it does lock it, B will fail in some way). Lets say instance A is not complete before instance B starts. A will then finish up and the document will have only A's new data. B will have started after A but before it was complete so if it finishes after A, it will nuke the changes made by process A because they were not yet loaded when process B initiated the load.
So I could use 3 documents Process A could then load DocumentA that produces qvd_A. Process B loads DocumentB producing qvd_B. My third document, MyDashboard could then integrate qvd_A and qvd_B data. Problem here is when is it safe to load data into MyDashboard? If A calls MyDashboard then it might collide with process B writing to qvd_B and vice versa if B calls MyDashboard.
So, again! Any commands that can help me here or perhaps other strategies to handle this (other than strategies that involve changes to process A and B themselves).
