Common dynamic views and dictionary tables in Oracle

The following lists common data dictionaries and dynamic performance views:
I. DBA's most common data dictionary

Dba_data_files: Used to query information about database files.
Dba_db_links: includes all database links in the database, that is, databaselinks.

Dba_extents: information about all partitions in the database
Dba_free_space: Free partitions in all tablespaces

Dba_indexs: description of all indexes in the database
Dba_ind_columns: compression of index columns on all tables and aggregation

Dba_objects: all objects in the database
Dba_rollback_segs: rollback segment description

Dba_segments: storage space of all database segments in Segments
Dba_synonyms: Query synonym Information

Dba_tables: description of all data tables in the database
Dba_tabespaces: Information about tablespaces

Dba_tab_columns: All table descriptions, views, and clustered Columns
Dba_tab_grants/privs: Permission granted to the object
Dba_ts_quotas: Quota of all user tablespaces
Dba_users: information about all users of data
Dba_views: Text of all views in the database

2. DBA's most common dynamic performance View

V $ datafile: the data file used by the database
V $ librarycache: shares the management information of SQL statements in the pool.
V $ lock: sets all object lock information by accessing database sessions.
V $ log: extract information about redo log groups from the Control File
V $ logfile information about the instance resetting the log group file name and its location
V $ parameter: value of all items in the initialization parameter file
V $ process: information about the current process
V $ rollname: rollback segment information

V $ rollstat: Online rollback segment statistics
V $ rowcache: In-memory data dictionary activity/performance information

V $ session: session information
V $ sesstat: Report the statistics of the current session in V $ session

V $ sqlarea: displays statistics of the current cursor in the shared pool. The cursor is a memory area and is opened when Oracle processes SQL statements.

V $ statname: Meaning of each statistics reported in V $ sesstat
V $ sysstat: system statistics based on the current operation session
Article Source: feino Network (www.firnow.com): http://dev.firnow.com/course/7_databases/oracle/oraclejs/20100721/481672.html