administration guide 11g(16)

oracle 11g管理篇

Online Table Redefinition Examples..........................................................................................20-46 Privileges Required for the DBMS_REDEFINITION Package...............................................20-52 Researching and Reversing Erroneous Table Changes................................................................20-52 Recovering Tables Using Oracle Flashback Table........................................................................20-53 Dropping Tables..................................................................................................................................20-54 Using Flashback Drop and Managing the Recycle Bin...............................................................20-54 What Is the Recycle Bin?..............................................................................................................20-55 Enabling and Disabling the Recycle Bin....................................................................................20-56 Viewing and Querying Objects in the Recycle Bin..................................................................20-56 Purging Objects in the Recycle Bin.............................................................................................20-57 Restoring Tables from the Recycle Bin.......................................................................................20-58 Managing Index-Organized Tables ................................................................................................20-59 What Are Index-Organized Tables?...........................................................................................20-59 Creating Index-Organized Tables...............................................................................................20-60 Maintaining Index-Organized Tables........................................................................................20-64 Creating Secondary Indexes on Index-Organized Tables.......................................................20-66 Analyzing Index-Organized Tables...........................................................................................20-67 Using the ORDER BY Clause with Index-Organized Tables..................................................20-68 Converting Index-Organized Tables to Regular Tables..........................................................20-68 Managing External Tables.................................................................................................................20-68 About External Tables..................................................................................................................20-69 Creating External Tables..............................................................................................................20-70 Altering External Tables...............................................................................................................20-72 Preprocessing External Tables.....................................................................................................20-73 Dropping External Tables............................................................................................................20-74 System and Object Privileges for External Tables....................................................................20-74 Tables Data Dictionary Views ..........................................................................................................20-75 21Managing Indexes

About Indexes........................................................................................................................................21-1 Guidelines for Managing Indexes.....................................................................................................21-2 Create Indexes After Inserting Table Data..................................................................................21-2 Index the Correct Tables and Columns.......................................................................................21-3 Order Index Columns for Performance.......................................................................................21-3 Limit the Number of Indexes for Each Table..............................................................................21-4 Drop Indexes That Are No Longer Required ............................................................................21-4 Indexes and Deferred Segment Creation.....................................................................................21-4 Estimate Index Size and Set Storage Parameters........................................................................21-4 Specify the Tablespace for Each Index.........................................................................................21-5 Consider Parallelizing Index Creation.........................................................................................21-5 Consider Creating Indexes with NOLOGGING........................................................................21-5 Understand When to Use Unusable or Invisible Indexes.........................................................21-6 Consider Costs and Benefits of Coalescing or Rebuilding Indexes.........................................21-7 Consider Cost Before Disabling or Dropping Constraints........................................................21-8 Creating Indexes....................................................................................................................................21-8 Creating an Index Explicitly..........................................................................................................21-9 Creating a Unique Index Explicitly..............................................................................................21-9

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