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Showing posts from November, 2016

Speed up Data Pump Import by suppressing redo generation

Customer Request : Import 20GB  Dump file without downtime(Without changing into noarchivelog mode). Problem: Database running in Archive log mode  and my archive destination size is very limited. Solution: Using  transform=disable_archive_logging:Y we can avoid redo generation and it will speedup import. Test:  Without Feature:  ============  Before Import:  SQL> select * from v$recovery_area_usage where FILE_TYPE='ARCHIVED LOG'; FILE_TYPE               PERCENT_SPACE_USED PERCENT_SPACE_RECLAIMABLE NUMBER_OF_FILES     CON_ID ----------------------- ------------------ ------------------------- --------------- ---------- ARCHIVED LOG                          1.74                         0               7          0 After Import:  SQL> set linesize 400 SQL> select * from v$recovery_area_usage where FILE_TYPE='ARCHIVED LOG'; FILE_TYPE               PERCENT_SPACE_USED PERCENT_SPACE_RECLAIMABLE NUMBER_OF_FILES     CON_ID ------------------

IMPDP is Taking Long Time at defining state

IMPDP is Taking Long Time at defining state with SYS User. Defining State itself taking more than 3 hours and actual data import finishing in 1 hour. We tried setting all performance parameters but no luck. Note: We are doing import using sys user in 12c Database (Exported from 11g Database). After struggling one week still no luck :( Solution :  we tried import with  system user by mistake and defining state completed in 2 Minutes :) use SYSTEM, not SYS on datapump. SYS is only for the legacy exp/imp.  From 12c Use SYSTEM user  to avoid Import performance issues. impdp system/manager dumpfile=test:filename.dmp logfile=test:filename.log

Oracle Database 12.2 books

All Database 12.2 Books link: http://docs.oracle.com/database/122/nav/portal_booklist.htm

Oracle Database 12.2.0.1 New Init Parameters

Oracle Database 12.2.0.1 is available now in the Oracle Cloud. And this is the list of 46 new init.ora/spfile parameters compared to Oracle Database 12.1.0.2 - including the links (where possible) to the Oracle Database 12.2 Reference documentation. Parameter Description allow_global_dblinks LDAP lookup for DBLINKS allow_group_access_to_sga Allow read access for SGA to users of Oracle owner group approx_for_aggregation Replace exact aggregation with approximate aggregation approx_for_count_distinct Replace count distinct with approx_count_distinct approx_for_percentile Replace percentile_* with approx_percentile asm_io_processes number of I/O processes per domain in the ASM IOSERVER instance autotask_max_active_pdbs Setting for Autotask Maximum Maintenance PDBs awr_pdb_autoflush_enabled Enable/Disable AWR automatic PDB flushing cdb_cluster [undocumented if TRUE startup in CDB Cluster mode cdb_cluster_name [undocumente