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Thursday, January 14, 2010

Read-Only Tablespaces

Read-Only Tablespaces

ALTER TABLESPACE userdata READ ONLY;

• Tablespace available only for read operations
• Objects can be dropped from tablespace
• Making tablespaces read-only causes a checkpoint on the data files of the tablespace

You can drop items, such as tables and indexes, from a read-only tablespace, because these commands affect only the data dictionary. This is possible because the DROP command
updates only the data dictionary, but not the physical files that make up the tablespace. For
locally managed tablespaces, the dropped segment is changed to a temporary segment, to
prevent the bitmap from being updated.

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