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ORACLE8i- P5: We want information information.” Possibly you recognize these words as the primary interest of a somewhat clandestine group, and as told by a character called Number 2 to Patrick McGoohan’s character Number 6 (in the old TV show The Prisoner). Indeed, in this day, information is king, and the speedy, accurate, and reliable retrieval of this information is paramount. | 150 I CHAPTER 4 THE DATA DICTIONARY Now grant select on the dba_data_files view to scott. SQL grant select on dba_data_files to scott Grant succeeded. SQL connect scott tiger Connected. SQL alter procedure get_all_bytes compile Procedure altered. SQL set serveroutput on SQL exec get_all_bytes Total bytes 141557760 PL SQL procedure successfully completed. Now create a procedure that runs with the rights of the owner Create the procedure as SYS because it owns the tables. We could also create an account and grant each table to it directly. SQL connect sys change_on_install Connected. CREATE OR REPLACE PROCEDURE get_all_bytes AUTHID DEFINER AS total_bytes NUMBER BEGIN SELECT SUM bytes INTO total_bytes FROM dba_data_files DBMS_OUTPUT.PUT_LINE Total bytes total_bytes END Procedure created. SQL grant execute on get_all_bytes to scott Grant succeeded. SQL connect scott tiger Connected. SQL set serveroutput on SQL exec sys.get_all_bytes Total bytes 249561088 Please purchase PDF Split-MJe 9e n wwwi.wypdfecom to removebihis watermark. USING THE ORACLE DATA DICTIONARY 151 Using the Oracle Data Dictionary Now that you know what the data dictionary is and how it came to be we urge you not to stop here Don t fall into the trap of being a DBA who doesn t know how to use your data dictionary to effectively manage your database. Unfortunately many DBAs are not comfortable with the data dictionary s tables and views and don t use them regularly. This may be because they learned to administer the database itself through a GUI tool such as Oracle s Enterprise Manager which reduces the need to refer to these tables. You ll be a better DBA however when you know how to navigate a pro- u w ductive course through the data dictionary and its contents. Appendix H is a quick reference to all the data dictionary and dynamic performance views. PART I NOTE Beyond its maintenance as a result of Oracle s DDL operations the data dictionary is also used during recursive SQL operations. When you .
