oracle internal table

internal RDBMS table

X$ : encrypted, sysdba only, fundation of internal mechanism.
example: X$KVIT

Data dictionary(table)

%$ : for storing database structure and definition, created by sql.bsp and $ORACLE_HOME/rdbms/admin
example: OBJ$

static data dictionary(view)

more stable than DD, based on X$% and %$.
A user have different levels of SDD.

type desc example
user_% objects that belong to user own user_tables
all_% objects that not belong to user but could access to all_tables
dba_% all table, only for sysdba role dba_users

dynamic performance view(view)

Including and reflect performance of system, dynamic, based on X$%

type desc example
GV$% including all instances GV$METRIC
V$% local instance only V$METRIC

order of accessing

  1. analyse object name
  2. the table and view of user own
  3. private synonym
  4. public synonym
  5. throw ORA-00942(cannot find object)

oracle internal table
https://rug.al/2015/2015-01-16-oracle-internal-table/
Author
Rugal Bernstein
Posted on
January 16, 2015
Licensed under