Tuning trend

Over the last 20 years, there has been a noticeable trend when it comes to improving database performance. Techniques are developed which sacrifice storage to improve performance. The common index is the first example of this. The index is much smaller in size and can dramatically improve performance of queries. Materialized views are copies of the data stored optimally to improve performance. Locally managed tablespaces reduce fragmentation but can waste storage. A very large UNDO tablespace can enable flash back recovery, saving time when recovering from user errors. Database flashback consumes a large amount of storage and enables faster database rollback capabilities. Recovery performance is improved at the expense of an increase in storage. For a data warehouse, for every byte of actual data, the rough rule of thumb is to allow for 8 bytes of additional storage for indexing and other objects used to improve performance. The mantra is "disk is cheap". In comparison to memory...