Given that we can specify 5 different parameters (USER MEMBERNAME, ROLE MEMBERNAME, WLM_LABEL, WLM_CONTEXT, START_TIME/END_TIME) – there must be a prioritisation mechanism in order to decide which condition gets selected. This mechanism is called Parameter Weighting in Azure Synapse and it assigns the following weight to each of those parameters:
USER = 64
ROLE = 32
WLM_LABEL = 16
WLM_CONTEXT = 8
START_TIME/END_TIME = 4
meaning that if the Workload Classifier fits into the timeframe START_TIME/END_TIME, WLM_LABEL & ROLE – it will receive 52 points = 4 + 16 + 32,
while a different Workload Classifier that fits into WLM_CONTEXT & USER will get 72 points = 8 + 64, thus will prevail and will be selected over the first Workload Classifier.
Azure Synapse Analytics (including when it was known as SQL Data Warehouse) has had some resource governor-related things I’ve wanted in the box product for a while, including labels (which are better than using application name).