oracle 11g管理篇

15Managing Datafiles and Tempfiles

Guidelines for Managing Datafiles...................................................................................................15-1 Determine the Number of Datafiles.............................................................................................15-2 Determine the Size of Datafiles.....................................................................................................15-3 Place Datafiles Appropriately.......................................................................................................15-4 Store Datafiles Separate from Redo Log Files.............................................................................15-4 Creating Datafiles and Adding Datafiles to a Tablespace ...........................................................15-4 Changing Datafile Size........................................................................................................................15-5 Enabling and Disabling Automatic Extension for a Datafile....................................................15-5 Manually Resizing a Datafile........................................................................................................15-6 Altering Datafile Availability.............................................................................................................15-6 Bringing Datafiles Online or Taking Offline in ARCHIVELOG Mode...................................15-7 Taking Datafiles Offline in NOARCHIVELOG Mode...............................................................15-7 Altering the Availability of All Datafiles or Tempfiles in a Tablespace.................................15-8 Renaming and Relocating Datafiles..................................................................................................15-8 Procedures for Renaming and Relocating Datafiles in a Single Tablespace..........................15-9 Procedure for Renaming and Relocating Datafiles in Multiple Tablespaces.......................15-10 Dropping Datafiles.............................................................................................................................15-11 Verifying Data Blocks in Datafiles..................................................................................................15-12 Copying Files Using the Database Server......................................................................................15-12 Copying a File on a Local File System........................................................................................15-13 Third-Party File Transfer.............................................................................................................15-14 File Transfer and the DBMS_SCHEDULER Package...............................................................15-15 Advanced File Transfer Mechanisms.........................................................................................15-15 Mapping Files to Physical Devices..................................................................................................15-15 Overview of Oracle Database File Mapping Interface............................................................15-16 How the Oracle Database File Mapping Interface Works.......................................................15-16 Using the Oracle Database File Mapping Interface..................................................................15-20 File Mapping Examples................................................................................................................15-23 Datafiles Data Dictionary Views......................................................................................................15-25 16 Managing Undo

What Is Undo?........................................................................................................................................16-1 Introduction to Automatic Undo Management ..............................................................................16-2 Overview of Automatic Undo Management..............................................................................16-2 About the Undo Retention Period................................................................................................16-3 Setting the Minimum Undo Retention Period................................................................................16-5 Sizing a Fixed-Size Undo Tablespace................................................................................................16-6 The Undo Advisor PL/SQL Interface..........................................................................................16-7 Managing Undo Tablespaces..............................................................................................................16-7 Creating an Undo Tablespace.......................................................................................................16-8 Altering an Undo Tablespace........................................................................................................16-9 Dropping an Undo Tablespace.....................................................................................................16-9 Switching Undo Tablespaces.......................................................................................................16-10 Establishing User Quotas for Undo Space.................................................................................16-10 Managing Space Threshold Alerts for the Undo Tablespace.................................................16-11

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