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Showing posts from December, 2016

Analyze pluggable database with Panorama

Panorama now supports analysis of pluggable databases (PDB) too. Visibility of informations in CDB and PDB There are different informations visible wether you are selecting from DBA_xx-views or CDB_xx-views and your are connected to CDB or PDB Role / user connected Container-DB (CDB / root) Pluggable database (PDB) Kind of views CDB_xx DBA_xx CDB_xx DBA_xx system all PDBs including root all PDBs including root nothing your current PDB user (SELECT ANY DICTIONARY) all PDBs including root root CDB nothing your current PDB Posted on  "Analyze pluggable database with Panorama"

Don’t flood Oracle-DB’s result cache

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Caching SQL result sets or PL/SQL function results is very easy by done simply adding hint or flag “RESULT_CACHE”. Without monitoring the usage of result cache this may lead to overbooking the size of result cache. In excessive manner flooding the result cache with new entries may result in significant latch waits. This latch waits will influence other concurrent sessions and occur also for sessions using only few result cache entries. You should pay attention to size result cache according to your needs and avoid massive crowding out. So using only 80% to 90% of result cache is a good rule of thumb to avoid the risk of latch waits on result cache. Example problem: Consider the following PL/SQL-Function that computes something possibly time dependent: FUNCTION getCachedValue p_Parameter1 IN NUMBER, p_Parameter2 IN NUMBER DEFAULT NULL, p_Date IN DATE DEFAULT SYSDATE ) RETURN VARCHAR2 PARALLEL_ENABLE RESULT_CACHE; With usage in PL/SQL code but ignoring the time depen