The Oracle system catalog is comprised of tables and views which allow the user to obtain information about the database, such as what other tables and views are available, their attributes, constraints, etc. Oracle has hundreds of available system catalog relations, only some of which are available to the average user (as many are intended for use only by qualified database administrators). .
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The Oracle system catalog is comprised of tables and views which allow the user to obtain information about the database such as what other tables and views are available their attributes constraints etc. Oracle has hundreds of available system catalog relations only some of which are available to the average user (as many are intended for use only by qualified database administrators). .
Oracle catalog consists of the metadata about objects like tables synonyms views etc. Oracle catalog is read by oracle when the database is getting up. Archive log as the backup or a copy of the redolog files. Archive logs are used to recover the database or whenever the log mining is required to perform.
Oracle System Catalog is comprised of tables views that provide user to obtain information about the database for eg : user_catalog user_views user_tables.
Where as Archive Log Files are offline copies of Online Redo Log Files meaning :
Once the Online Redo Log files are filled if database is running in archive log mode archiver saves these files to the archive destination.
System Created Tables Which Contain Statistics and Useful Data Collected Automatically by the Database Engine to Help the Administrator or the regular users. There Are Several Kinds Of Catalogs :
V$_Catalog dba_Catalog User_Catalog
RMAN Catalog:
Catalog Created By Rman manually After Enabling Archive Log Which Contain Data Regarding The BackUp/Recovery Process. ----------------------------------- Archive Log: Member Of The Archive Group Contain all committed data is very essential in recovering database to the last minute before disaster. DataBase Archiver: Responsible For Creating Archive Log Files .
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