- Could I use both the traditional and RMAN backup at the same time?
- Do I need to re-index the table if there is a change in the structure?
- I have a table ABC with columns A1, A2, A3, A4, A5, A6 and A7. My index is A1, A2, A3, A5. When I run a query using only A1, A5 in the where clause, is it using the index?
You can definitely use the traditional (user-managed) hot and cold backups in conjunction with RMAN backups. But recovery from these different backups is different. RMAN can only use the RMAN backup for recovery, similarly for the user-managed backups. Make sure you practice recovery from each backup type under a variety of scenarios.
You do not need to re-index a table if you change the table's structure unless your structural change involves the index. Simply adding a column to a table will not affect any exisiting indexes. Dropping a column can affect an index if the index uses that column.
The only way to know for sure if your query is using any index is to run the query through EXPLAIN PLAN. This will tell you how Oracle is executing the query. Depending on your configuration, the index may or may not be used.
This was first published in February 2006