Oracle 11gR2 Deferred Segment Creation

Oracle Deferred Segment Creation new feature in Oracle Database 11g Release 2.
Creating a non-partitioned heap-organized table in a locally managed tablespace, the table segment creation is deferred until the first row is inserted. In addition, creation of segments is deferred for any LOB columns of the table, any indexes created implicitly as part of table creation, and any indexes subsequently explicitly created on the table.

Placing a Table in Read-Only Mode in Oracle 11g

New in Oracle 11g, you can place a table in read-only mode with the ALTER TABLE...READ ONLY statement, and return it to read/write mode with the ALTER TABLE...READ WRITE statement. An example of a table for which read-only mode makes sense is a configuration table. If your application contains configuration tables that are not modified after installation and that must not be modified by users, your application installation scripts can place these tables in read-only mode. The table is in read-only mode, operations that attempt to modify table data are disallowed.