Oracle Internal Arch. (contd.)
- a tablespace can be made read-only using ALTER TABLESPACE command; no backup required. It is not modified. This is useful in data warehousing.
Transportable tablespace : allows transfer of actual data files from one DB to another without explicitly unloading and reloading data row-by-row. The steps to carry this out are :
- export metadata of tablespace contents from data dictionary.
- transfer exported file with copies of data files.
- these are incorporated in new DB.
Optionally, a bit-map can be created to indicate free extents within a tablespace called locally managed tablespace.