Like anything in life, indexes require maintenance. Over time, the performance benefits of indexes can wane or, through data modifications, their sizes and the underlying statistics can drift and bloat. To prevent these issues, indexes must be maintained. If you do so, your database will remain a lean, mean query-running machine.
When it comes to maintenance, there are five areas to consider:
Index fragmentation
Heap bloat and forwarding
Columnstore fragmentation
Statistics
In-memory statistics
Each plays a key role in maintaining a properly indexed and well-performing database.
This chapter ...
