E – TRUNCATE Statement
You can use the TRUNCATE statement to remove data. It doesn’t log the deletion of the data and doesn’t enable a ROLLBACK statement because there isn’t any logging of the deletion. It does leave the definition of a table intact.
This is helpful when you don’t need the data but do need the table structure. The most frequent use of this command is for tables that contain derived data. Derived data is calculated from source data, and thereby easy to replace. There are often a number of temporary reporting tables that hold derived data to speed query resolution.
Since Oracle 10g, these typically evolve into materialized views because they can be refreshed easily and less expensively than truncating and repopulating tables with derived data.
TRUNCATE TABLE item_rental_histogram; |
