Setup/Intro: I have created a fairly complex QlikView application which utilizes 3 Tiered Architecture (or 4 Tiered, based on how you look at it) due to the required reload times and amount of rows.
At a high level I have the following Tiers/layers
Tier1: Load raw DB data and store into QVDs
Layer 1: Load data from Raw database tables and store in separate QVDs
Layer 2: Apply first level of staging/transformations
Layer 3: Apply second level of staging/transformations
Tier3/4: Data model and UI
Layer 4: Create data model (star schema) using data from previous layers
Layer 5: Binary load data model (Layer 4) into UI
I am finding it difficult to maintain this type of architecture when say, for example, I change or add a field in layer 2. If this happens I have to change layers 3, 4 and 5. Furthermore, I am now working on creating additional applications utilizing data from either layer 2 or 3 as a starting point, so there will be even more scripts which will need to be updated when a change occurs. What are some ways to make maintenance easier? One of the main type of examples of changes would be adding or renaming fields.