問題文
A rail freight operator's analytic queries over the shipment history table, which carries a clustered columnstore index, have slowed month after month of trickle loads and deletes. Maintenance must run while the reporting shift continues, and the team wants to spend as few resources as possible. Which maintenance operation fits that requirement?
選択肢
- Update the statistics on the table, because a stale distribution is what makes a scan of a fragmented index slow.
- Drop the columnstore index and create it again during the reporting shift, because creating the index afresh does compact the rows that are still sitting in the intermediate store, and it is the only operation that reaches every row group.
- Rebuild the index with ALTER INDEX, because only a rebuild can move rows out of the intermediate store into the compressed store.
- Reorganize the index with ALTER INDEX, because it always runs online, defragments the index, and in most cases gives results similar to a rebuild with lower resource consumption.