2009.01.11_18_19 DataDictionary&DynamicPView

■Built-In Database Objects

　・Data dictionary

　・Performance tables

  ・PL/SQL packages

  ・Database event triggers

●Data dictionary

 　Strored in the SYSTEM tablespace

   Owned by the User SYS

   Maintained by the Oracle server

   Read-only (Select)

   Listed in Dictionary

  Contains Two parts :

   ・Base tables  (Created with CREATE DATABASE) sql.bsq

　　・Data dictionary views(Created with the catalog.sql script)

  Containts :

    ・Logical and Physical dababase Structures

　　・Dafinitions and space allocations of objects

    ・Integrity constrants

    ・Users

　　・Roles

　　・Privileges

   ・Auditing

　How to be Used:　

   Modified when DDL is executed

  DD View catalogories:

   ・DBA_

　　・ALL_

　　・User_

        Oracle Ducuments

　　　SQL>select * from dba_objects;

     SQL>select * from all_objects;

     SQL>select * from users_objects;

●Dynamic Performance Tables(V$,GV$,XV$)

  virtual tables;

  Information is accessed from memory and control file;

  Used to monitor and tune the database

  Owned by SYS

  Listed in v$FIXED_TABLE