Oracle *daily* TidBits” (#oratidbit) published on Facebook, Twitter and Google+ during weekdays in January 2017. You will also see these tidbits, one tidbit at a time, for each page refresh on the right side of this blog as well… Hope you find these helpful to learn something new or to remind you of its existence and use.

#oratidbit #DB12cR2 In 12.2, Local temporary tablespace can be created using LOCAL TEMPORARY TABLESPACE clause of CREATE TABLESPACE. In RAC environment, local temporary tablespaces store a separate, nonshared temp files for each database instance, which can improve I/O performance. A local temporary tablespace must be a BIGFILE tablespace.
#oratidbit A non-partitioned table in Oracle #DB12cR2 can be converted to a partitioned table by using the MODIFY clause of ALTER TABLE. MODIFY PARTITION clause specifies the partition properties.
#oratidbit Starting with #Exadata release 12.1.2.2.0, Oracle Exadata database nodes, Oracle Exadata Virtual Server nodes (dom0), and Oracle Exadata Virtual Machines (domU) can be updated, rolled back, and backed up using patchmgr. Using patchmgr enables you to run a single command to update multiple nodes; you do not need to run dbnodeupdate.sh separately on each node. patchmgr can update the nodes in a rolling or non-rolling fashion.
#oratidbit #db12cR2 The OPTIMIZER_ADAPTIVE_FEATURES initialization parameter is desupported in Oracle Database 12c Release 2 (12.2.0.1).
#oratidbit #db12cR2 The ON STATEMENT refresh mode refreshes materialized views every time a DML operation is performed on any base table, without the need to commit the transaction. This mode does not require you to maintain materialized view logs on the base tables.
#oratidbit In #db12c the SIMILAR value for the CURSOR_SHARING initialization parameter is deprecated. Use FORCE instead.
#oratidbit #db12cR2 New initialization parameter DATA_GUARD_SYNC_LATENCY, enables you to define the maximum amount of time (in seconds) that the primary database may wait before disconnecting subsequent standby destinations after at least one synchronous standby has acknowledged receipt of the redo.
#oratidbit #db12cR2 Using initialization parameter ENABLED_PDBS_ON_STANDBY specify a subset of pluggable databases (PDBs) for replication on a physical standby of a multitenant container database (CDB). In 12.1, you had to replicate either all PDBs or none.
#oratidbit #db12cR2 Password file changes done on the primary database are now automatically propagated to standby databases. The only exception to this is far sync instances. Updated password files must still be manually copied to far sync instances because far sync instances receive redo, but do not apply it.
#oratidbit #db12cR2 DBMS_JOB package is deprecated, and may be desupported in a future release. Move to DBMS_SCHEDULER.
#oratidbit #db12cR2 By default, permissions to read and write to the System Global Area (SGA) are limited to the Oracle software installation owner only. In previous releases, both the Oracle installation owner account and members of the OSDBA group had access to shared memory.
#oratidbit #db12cR2 Initialization parameter ALLOW_GROUP_ACCESS_TO_SGA determines if the Oracle Database installation owner account is the only user that can read and write to the database System Global Area (SGA), or if members of the OSDBA group can read the SGA. In Oracle Database 12c Release 2 (12.2), the default value for this parameter is FALSE.
#oratidbit #db12cR2 Parallel Upgrade Utility using command-line batch script catupgrd.sql is no longer distributed with 12.2. Run the parallel upgrade utility by using command dbupgrade on Linux/Unix and dbupgrade.com for Windows.
#oratidbit Oracle #DB12c Feature: In-database archiving is enabled by using the attribute ROW ARCHIVAL in the CREATE TABLE or ALTER TABLE statements. Invisible column ORA_ARCHIVE_STATE is added to the table with default value 0 (not archived).
#oratidbit #db12cR2 The SYSRAC administrative privilege is used by the Clusterware agent in its connection to the database on behalf of Oracle RAC utilities, such as SRVCTL. The SYSRAC privilege provides only the minimal privileges necessary for performing day-to-day Oracle RAC operations.
#oratidbit #db12cR2 SQL*Plus supports command history; SET HISTORY enables users to run, edit, or delete previously used SQL*Plus, SQL, or PL/SQL commands from the history list in the current session.
#oratidbit #db12cR2 The SET MARKUP SQL*Plus command supports the display of data in CSV format. Produce output in HTML or CSV format.
#oratidbit #db12cR2 The SET FEEDBACK ONLY SQL*Plus command returns just the number of rows returned by the query without displaying the query result.
#oratidbit #db12cR2 CDB root and individual PDBs store, view, and manage AWR data. You can take an AWR snapshot at a CDB-level (root), as well as at a PDB-level (individual PDBs). In 12cR1, AWR snapshots are at CDB level (root) and included information from CDB and all PDBs.
#oratidbit #db12cR2 When you take AWR snapshot at CDB level, snapshot data is stored in SYSAUX tablespace of CDB. The PDB-level snapshot data is stored in the SYSAUX tablespace of a PDB.

Oracle *daily* TidBits” (#oratidbit) published on Facebook, Twitter and Google+ during weekdays in December 2016. You will also see these tidbits, one tidbit at a time, for each page refresh on the right side of this blog as well… Hope you find these helpful to learn something new or to remind you of its existence and use.

OraTidBit
#oratidbit #DB12cR2 You can capture Automatic Workload Repository (AWR) data for Oracle Active Data Guard standby databases. This feature enables performance tuning of Oracle Active Data Guard standby databases.
#oratidbit #DB12cR2 INACTIVE_ACCOUNT_TIME initialization parameter automatically locks the database user account who has not logged in to the database instance in a specified number of days.
#oratidbit #db12cR2 You can prioritize the PDBs in a CDB when you upgrade the CDB. The PDBs with higher priority are upgraded before PDBs with lower priority.
#oratidbit #db12cR2 A CDB can run in local undo mode or shared undo mode. Local undo mode means that every container in the CDB uses local undo. Shared undo mode means that there is one active undo tablespace for a single-instance CDB.
#oratidbit #db12cR2 In 12.2, tables with BFILE columns can be redefined online.
#oratidbit #db12cR2 In 12.2, Query the V$ONLINE_REDEF view to monitor the progress of an online table redefinition operation.
#oratidbit #db12cR2 In 12.2, SYSRAC is a new administrative privilege for tasks related to Oracle Real Application Clusters (#Oracle #RAC) operations.
#oratidbit #DB12cR2 ALLOW_GROUP_ACCESS_TO_SGA is new parameter and controls group access to shared memory on UNIX platforms. The default value is false, which means that database shared memory is created with owner access only. In Oracle Database releases prior to Oracle Database 12c Release 2 (12.2.0.1), database shared memory was created with owner and group access.
#oratidbit #DB12cR2 AWR_PDB_AUTOFLUSH_ENABLED is new parameter and enables you to specify 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.The default value of AWR_PDB_AUTOFLUSH_ENABLED is false. Thus, by default, automatic AWR snapshots are disabled for all the PDBs in a CDB. When you change the value of AWR_PDB_AUTOFLUSH_ENABLED in the CDB root, the new value takes effect in all the PDBs in the CDB. Therefore, if you change the value of AWR_PDB_AUTOFLUSH_ENABLED in the CDB root to true, the value of AWR_PDB_AUTOFLUSH_ENABLED is also changed to true in all of the PDBs, so that automatic AWR snapshots are enabled for all the PDBs. You can also change the value of AWR_PDB_AUTOFLUSH_ENABLED in any of the individual PDBs in a CDB, and the value that is set for each individual PDB will be honored. This enables you to enable or disable automatic AWR snapshots for individual PDBs.
#oratidbit #DB12cR2 ENABLE_AUTOMATIC_MAINTENANCE_PDB is new parameter and can be used to enable or disable the running of automated maintenance tasks for all the PDBs in a CDB or for individual PDBs in a CDB. When you change the value of ENABLE_AUTOMATIC_MAINTENANCE_PDB in the CDB root, the new value takes effect in the root and in all the PDBs in the CDB. You can also change the value of ENABLE_AUTOMATIC_MAINTENANCE_PDB in any of the individual PDBs in a CDB, and the value that is set for each individual PDB will be honored. This enables you to enable or disable automated maintenance tasks for individual PDBs.
#oratidbit #DB12cR2 ENABLED_PDBS_ON_STANDBY is new parameter and specifies which pluggable databases (PDBs) to replicate on an Oracle Data Guard standby database. The asterisk (*) and question mark (?) wildcard characters are supported.
#oratidbit #DB12cR2 REMOTE_RECOVERY_FILE_DEST is new parameter and specifies a directory from which to read archive log files during a pluggable database (PDB) refresh operation if the source is not available.
#oratidbit #DB12cR2 UNIFORM_LOG_TIMESTAMP_FORMAT is new parameter and specifies that a uniform timestamp format be used in Oracle Database trace (.trc) files. When the value of UNIFORM_LOG_TIMESTAMP_FORMAT is TRUE, the format used for timestamps in trace files is standardized on universal time with millisecond precision. When the value of UNIFORM_LOG_TIMESTAMP_FORMAT is FALSE, trace files include a mix of timestamps using different precisions, with some timestamps showing local time and other timestamps showing universal time.
#oratidbit Before you create a DBaaS instance on Oracle Database #Cloud (#DBaaS), you must setup an SSH public/private key pair to connect to compute node and optionally Oracle storage cloud service container to backup the database to cloud.
#oratidbit Use dbaascli utility on Oracle #DBaaS cloud deployments to perform a variety of life-cycle and administration operations including patching, database recovery and data guard switchover.
#oratidbit Use raccli utility #DBaaS cloud deployments that use Oracle Real Application Clusters (RAC) to perform a variety of life-cycle and administration operations including backup, recovery, patching, security configurations and so on.
#oratidbit Use dbpatchmdg utility #DBaaS cloud deployments that are configured with Oracle Data Guard to perform a variety of patching operations.
#oratidbit Use the oracle-dbcs-cli utility on your Linux computer to connect to Oracle Cloud and perform a variety of life-cycle and administration operations on Oracle Database Cloud Service deployments (non RAC).
#oratidbit To use #Oracle Database Backup Cloud Service you’ll subscribe to the service, install the Oracle Database Cloud Backup Module, and configure your environment to send backups to the cloud using familiar RMAN commands.
#oratidbit Oracle Database Exadata Express Cloud Service delivers a managed Oracle Database 12c Release 2 Enterprise Edition with options, running on Oracle Exadata engineered systems.
#oratidbit #DB12cR2 In 12.2, the maximum length for most database object names has increased from 30 bytes to 128 bytes.
#oratidbit #DB12cR2 In 12.2, you can encrypt undo tablespaces, temporary tablespaces, and the SYSTEM and SYSAUX tablespaces. Also, encrypt both offline and online tablespaces.

Oracle *daily* TidBits” (#oratidbit) published at https://www.facebook.com/oraclenotes on weekdays in May 2016. You will also see these tidbits, one tidbit at a time, for each page refresh on the right side of this blog as well… Hope you find these helpful to learn something new or to remind you of its existence and use…

#oratidbit 101: In a CDB, the UNDO_MANAGEMENT parameter must be AUTO. There is one active undo tablespace for a single-instance CDB. Cannot have separate UNDO tablespace for PDBs.
#oratidbit To create a service for a PDB using the SRVCTL utility, use the add service command and specify the PDB in the -pdb parameter. If you do not specify a PDB in the -pdb parameter when you create a service, then the service is associated with the root.
#oratidbit PDB management with Oracle EM Express is available starting with Oracle Database 12c Release 1 (12.1.0.2).
#oratidbit There is a default temporary tablespace for the entire CDB. You optionally can create additional temporary tablespaces for use by individual PDBs.
#oratidbit Specify STORAGE clause in CREATE PLUGGABLE DATABASE to specify the amount of storage that can be used by all tablespaces that belong to the PDB. Default is UNLIMITED.
#oratidbit Cluster Verification Utility (CVU) is a command-line tool that you can use for preinstallation and postinstallation checks of your cluster environment. OUI runs CVU after the Oracle Clusterware installation to verify the environment.
#oratidbit Oracle Cluster Registry (OCR) maintains cluster configuration information and configuration information about any cluster database within the cluster. The OCR contains information such as which database instances run on which nodes and which services run on which databases.
#oratidbit For a fixed-size undo tablespace, Oracle Database automatically tunes the system to give the undo tablespace the best possible undo retention. For an automatically extensible undo tablespace, Oracle Database retains undo data longer than the longest query duration and the low threshold of undo retention specified by the UNDO_RETENTION parameter.
#oratidbit Query V$UNDOSTAT.TUNED_UNDORETENTION to determine the amount of time for which undo is retained for the current undo tablespace.
#oratidbit To use Oracle Flashback Transaction Query feature, supplemental logging must be enabled in the database – ALTER DATABASE ADD SUPPLEMENTAL LOG DATA;
#oratidbit When upgrading your database, DBUA expects that both the source (pre-12c) Oracle home and the destination (new 12c) Oracle home are owned by the same user.
#oratidbit Starting with Oracle Database 12c, Oracle XML DB is a mandatory component of Oracle Database. You cannot uninstall Oracle XML DB, and there is no option to exclude it when you create an Oracle database.
#oratidbit Starting with Oracle Database 11g Release 2 (11.2), setting JOB_QUEUE_PROCESSES to 0 causes both DBMS_SCHEDULER and DBMS_JOB jobs to not run.
#oratidbit A Global Data Services (GDS) configuration and its global services are created and managed using the GDSCTL command-line interface. GDS is a highly effective solution for automatic workload management across a set of replicated databases.
#oratidbit Oracle NoSQL Database is available in Community Edition (CE) and Enterprise Edition (EE). Only EE has integration with Oracle Stack such as Oracle Database External Table Integration, Oracle Big Data SQL integration, and so on.
#oratidbit You can model data in Oracle NoSQL Database by using Tables, JSON schemas or a raw key-value interface. Tables are the easiest way to model data and they provide the highest level of abstraction.
#oratidbit Setting database initialization parameter STATISTICS_LEVEL to BASIC disables many Oracle Database features, including ADDM. Setting parameter CONTROL_MANAGEMENT_PACK_ACCESS to NONE also disables ADDM.
#oratidbit ADDM analysis of I/O performance partially depends on DBIO_EXPECTED, which is the average time it takes to read a single database block in microseconds – default is 10 milliseconds.
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