Specifying FORCE LOGGING Mode (82)

Some data definition language statements (such as CREATE TABLE) allow the
NOLOGGING clause, which causes some database operations not to generate redo
records in the database redo log. The NOLOGGING setting can speed up operations that
can be easily recovered outside of the database recovery mechanisms, but it can
negatively affect media recovery and standby databases.

Oracle Database lets you force the writing of redo records even when NOLOGGING has
been specified in DDL statements. The database never generates redo records for
temporary tablespaces and temporary segments, so forced logging has no affect for
objects.

指定強制日誌模式
1. 有些DDL語句可指定NOLOGGING子句 , 以此在默寫資料庫操作時將不產生重做日誌 .
對於該模式 , 在資料外的恢復機制下容易恢復 , 但對於介質恢復和備用資料庫模式則很難
2. 使用force logging , 即使是在DDL語句中包含NOLOGGING也會強制寫日誌
3. 對於臨時表空間和臨時段 , 資料庫不記重做日誌
4. 該模式對於物件無效

[@more@]