My terms aggregation (on a high cardinality field) with an inner cardinality aggregation takes about 23 seconds to complete (one node, one shard, 300,000 documents, keyword fields).
The equivalent SQL query using SQL server takes a few seconds at most.
Is it reasonable of me to make that comparison? Maybe SQL Server is just more suited for this kind of queries?
I posted a related question with much more detail on Stack Overflow (https://stackoverflow.com/q/44225038/1545350) if anyone cares to assist there as well.