Oracle Tidbits: March 2019 #oratidbit

Oracle *daily* TidBits” (#oratidbit) published on Facebook &Twitter, during weekdays in March 2019. Hope you find these helpful to learn something new or to remind you of its existence and use.

#oratidbit #db19c You can tune the Oracle Data Guard automatic outage resolution using DATA_GUARD_MAX_IO_TIME and DATA_GUARD_MAX_LONGIO_TIME parameters.
#oratidbit #db18c ASM database cloning provides cloning of Multitenant databases (PDBs). This feature works by leveraging ASM redundancy.
#oratidbit Passwords in database links are encrypted in #db18c. Oracle Data Pump handles the export and import of these passwords. Import operations from older versions and export operations to older versions can still be used.
#oratidbit #oraclecloud #thinkautonomous When using the OCI Console, starting on 3/7/2019, all ADW and ATP databases will appear in a single list view as Autonomous Databases with a new workload type column showing the type of Autonomous Database, namely “Data Warehouse” or “Transaction Processing”.
#oratidbit #db19c Pluggable databases (PDBs) are supported as a target database in RMAN Recovery Catalog and a virtual private catalog (VPC) user can be used to more granularly control permissions to perform backup and restore operations at a PDB level.
#oratidbit #orcldb Starting with 19c, the Oracle Database Client software is available as an image file for download and installation. Extract the image software into the Oracle Home directory and run the runInstaller script.
#oratidbit #db19c Starting with Oracle Grid Infrastructure 19c, the Oracle Grid Infrastructure installation wizard (gridSetup.sh) enables you to perform a dry-run mode upgrade to check your system’s upgrade readiness.
#oratidbit #db19c Data Pump Import supports wildcard dump file names for URL-based dump files maintained in cloud object stores. Note that the wildcard character can only be specified in the file-name component of the URL.
#oratidbit #db19c Starting with #db12c, ADDM is enabled by default in the root container of a multitenant container database (CDB). Starting with #db19c, you can also use ADDM in a pluggable database (PDB). AWR data on a PDB cannot be accessed from the CDB root.
#oratidbit #db19c ADDM does not work in a PDB by default, because automatic AWR snapshots are disabled by default in a PDB. To use ADDM in a PDB, enable automatic AWR snapshots in the PDB.
#oratidbit The #db18c resource manager directive PQ_TIMEOUT_ACTION enables the database administrator to specify the action to take on a parallel SQL statement that is timed out of the parallel SQL statement queue.
#oratidbit #nothingnew The UNION and UNION ALL statements can run several branches concurrently instead of working on them one-by-one – speeds up processing time and leads to better resource utilization.
#oratidbit #db19c Database users without SELECT_CATALOG_ROLE can generate and view SQL Monitor reports for their own SQL statements, including the execution plans and performance metrics. Good for developers.
#oratidbit #db19c SQL statements that are terminated by Oracle Database Resource Manager due to their excessive consumption of CPU and I/O resources can be automatically quarantined. The execution plans associated with the terminated SQL statements are quarantined to prevent them from being executed again.
#oratidbit #db19c In a multitenant database, you can use Oracle Database Vault to block common users (infrastructure DBAs, for example) from accessing local data in pluggable databases (PDBs).
#oratidbit #db12cR2 Parameter AUTOTASK_MAX_ACTIVE_PDBS specifies the maximum number of PDBs that can schedule automated maintenance tasks at the same time. By default, two PDBs and the CDB root can run tasks at the same time during a maintenance window.
#oratidbit #db12cR2 Parameter AWR_PDB_AUTOFLUSH_ENABLED specifies whether to enable or disable automatic Automatic Workload Repository (AWR) snapshots for all the PDBs in a CDB or for individual PDBs in a CDB. By default, automatic AWR snapshots are disabled for all the PDBs.
#oratidbit #nothingnew Unusable indexes and index partitions do not consume space in the database because they become segmentless. When you make an existing index unusable, its index segment is dropped.
#oratidbit #apex For testing and production instances, Oracle Application Express supports the ability to install a runtime version. This minimizes the installed footprint and privileges.
#oratidbit #nothingnew Database Smart Flash Cache feature (on #Solaris and #OracleLinux) is a transparent extension of the database buffer cache using solid state device (SSD) technology. The SSD acts as a Level 2 cache to the (Level 1) SGA.