OracleNotes

Tag: oratidbit

  • Oracle Tidbits – August 2018 #oratidbit

    Oracle Tidbits – August 2018 #oratidbit

    “Oracle *daily* TidBits” (#oratidbit) published on  Facebook, Twitter, and Google+ during weekdays in August 2018. Hope you find these helpful to learn something new or to remind you of its existence and use.

    #oratidbit When the value of UNIFORM_LOG_TIMESTAMP_FORMAT init parameter 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 USE_LARGE_PAGES init parameter is used to manage the database’s use of large pages for SGA memory. Value ONLY specifies that the instance will fail to start if large pages cannot be used for the entire SGA memory.
    #oratidbit MAX_MBPS init parameter enables you to set the maximum number of megabytes (MB) of I/Os issued per second on a per pluggable database (PDB) basis. This parameter is used to throttle PDB I/Os.
    #oratidbit Oracle Autonomous Transaction Processing (ATP) Cloud Service includes database migration utility to easily migrate from MySQL, PostgreSQL, SQL Server, and other databases.
    #oratidbit Oracle Autonomous Transaction Processing (ATP) automatically backs up your database. The retention period for backups is 60 days. You can restore and recover your database to any point-in-time in this retention period.
    #oratidbit In Oracle Autonomous Transaction Processing (ATP) the default data and temporary tablespaces for the database are configured automatically. Adding, removing, or modifying tablespaces is not allowed.
    #oratidbit In Oracle Autonomous Transaction Processing (ATP) database links to other databases are not allowed for enhanced security. Database links from other databases to ATP are allowed.
    #oratidbit In Oracle Autonomous Transaction Processing (ATP) a few initialization parameters can be modified, including OPTIMIZER_IGNORE_HINTS and OPTIMIZER_IGNORE_PARALLEL_HINTS.
    #oratidbit In Oracle Autonomous Transaction Processing (ATP) LONG and LONG RAW data types are not supported.
    #oratidbit #atp you can configure Autonomous Transaction Processing to terminate SQL statements automatically based on their runtime or the amount of IO they are doing. Use the procedure cs_resource_manager.update_plan_directive to set these rules.
    #oratidbit With centrally managed users (CMU) Oracle database users and roles can map directly to Active Directory users and groups without using Oracle Enterprise User Security (EUS) or another intermediate directory service.
    #oratidbit #db18c Setting ADG_ACCOUNT_INFO_TRACKING to GLOBAL maintains a single global copy of users account information across all Data Guard databases (primary and standby). Login failures across all databases count towards the maximum count and logins anywhere will be denied when the count is reached.
    #oratidbit Init parameter PARALLEL_DEGREE_LIMIT limits the degree of parallelism used by the optimizer to ensure that parallel server processes do not flood the system.
    #oratidbit Init parameter RESOURCE_MANAGE_GOLDENGATE determines whether Oracle GoldenGate apply processes in the database are resource managed. By default, Oracle GoldenGate apply processes in the database are not resource managed.
    #oratidbit Init parameter PDB_OS_CREDENTIAL determines the identity of the OS user employed when interacting with the OS from a PDB. Helps ensure that OS interactions are by a less powerful user and protects data belonging to one PDB from being accessed by users connected to another PDB.
    #oratidbit #ATP The tnsnames.ora file provided with the credentials zip file contains four database service names as high, medium , low, and parallel. The predefined service names provide different levels of performance and concurrency for ATP Cloud Service.
    #oratidbit Hash partitioned global indexes can improve the performance of indexes where a small number of leaf blocks in the index have high contention in multiuser OLTP environments.
    #oratidbit The awrgdrpi.sql SQL script generates an HTML or text report that compares detailed performance attributes and configuration settings between two selected time periods using specific databases and instances in an Oracle RAC environment.
    #oratidbit The ashrpti.sql SQL script generates an HTML or text report that displays ASH information for a specified duration for specified databases and instances in an Oracle Real Application Clusters (Oracle RAC) environment.
    #oratidbit V$RSRC_CONSUMER_GROUP shows CPU utilization statistics for each consumer group when the Oracle Database Resource Manager is running.
  • Oracle Tidbits – July 2018 #oratidbit

    Oracle Tidbits – July 2018 #oratidbit

    “Oracle *daily* TidBits” (#oratidbit) published on  Facebook, Twitter, and Google+ during weekdays in July 2018. Hope you find these helpful to learn something new or to remind you of its existence and use.

    #oratidbit #db18c To change a regular user (password authenticated) to schema only account, the user should not have any administrative privileges (SYSDBA, SYSRAC, etc.). Query administrative privileges in V$PWFILE_USERS.
    #oratidbit #db18c The ALTER DATABASE DICTIONARY statement can encrypt sensitive credential data in the SYS.LINK$ and SYS.SCHEDULER$_CREDENTIAL system tables.
    #oratidbit #db18c Though encrypting Sensitive Credential Data in the Data Dictionary feature makes use of Transparent Data Encryption (TDE), no need to have an Advanced Security Option license to perform the encryption, but need the SYSKM administrative privilege.
    #oratidbit #sqldev SQL Developer Web is bundled with Oracle Public Cloud Database Services. Access to SQL Developer Web is provided through schema-based authentication, after enabling the schema for SQL Developer Web.
    #oratidbit #sqldev You can use SQL Developer Web to monitor the CPU utilization, memory, storage, and operating system processes for the DBaaS compute node.
    #oratidbit #db18c To create a schema only account, replace the IDENTIFIED BY clause with NO AUTHENTICATION in a CREATE USER statement. You can grant system privileges and administrator roles to schema only accounts. A schema only account cannot log in to the database.
    #oratidbit #db18c To change a regular user (password authenticated) to schema only account, the user should not have any administrative privileges (SYSDBA, SYSRAC, etc.). Query administrative privileges in V$PWFILE_USERS.
    #oratidbit #db18c The ALTER DATABASE DICTIONARY statement can encrypt sensitive credential data in the SYS.LINK$ and SYS.SCHEDULER$_CREDENTIAL system tables.
    #oratidbit #db18c Though encrypting Sensitive Credential Data in the Data Dictionary feature makes use of Transparent Data Encryption (TDE), no need to have an Advanced Security Option license to perform the encryption, but need the SYSKM administrative privilege.
    #oratidbit #db18c Private temporary tables are temporary database objects that are automatically dropped at the end of a transaction or a session. A private temporary table is stored in memory and is visible only to the session that created it.
    #oratidbit Memory Guard is an Oracle Real Application Clusters (Oracle #RAC) environment feature to monitor the cluster nodes to prevent node stress caused by the lack of memory.
    #oratidbit Hang Manager is an Oracle #RAC environment feature that autonomously resolves hangs and keeps the resources available. It logs all detections and resolutions, provides SQL interface to configure sensitivity (Normal/High) and trace file sizes.
    #oratidbit You can upgrade only Oracle Enterprise Manager 13c Release 2 (13.2.0.0), 13c Release 1 (13.1.0.0), or 12c Release 5 (12.1.0.5) to 13c Release 3 (13.3.0.0).
    #oratidbit #db18c Each pluggable database (PDB) can now have its own keystore instead of there only being one keystore for the entire container database (CDB).
    #oratidbit The default value for an OFA-compliant path for the Oracle Clusterware home is: /u01/app/18.0.0/grid
    #oratidbit #oraclecloud Oracle Database Backup Cloud Service is used to store Oracle Database backups only. To store other types of backup, use Oracle Storage Cloud Service.
    #oratidbit #orcldb Transparent Application Continuity (TAC) transparently tracks and records session and transactional state so recoverable outages are hidden from users. This is done safely and with no reliance on application knowledge or code changes.
    #oratidbit Standby Nologging for Load Performance ensures that standbys receive nonlogged data changes with minimum impact on loading speed at the primary but at the cost of allowing the standby to have transient nonlogged blocks.
    #oratidbit #db18c RMAN can duplicate an unencrypted PDB or tablespaces within the PDB such that they are encrypted in the destination CDB. Use the AS ENCRYPTED clause of the DUPLICATE command to perform this duplication.
    #oratidbit #db18c The In-Memory Column Store supports population of external tables, enabling users to perform advanced analytical queries on external data stores.
    #oratidbit #db18c A scalable sequence is particularly efficient when used to generate unordered primary or unique keys for data ingestion workloads having high level of concurrency.
    #ortidbit FORWARD_LISTENER init parameter is useful when it is difficult to change an existing client connect string after a database move. Clients can continue to connect to their old listener, and the old listener forwards the connection to the new listener.
    #oratidbit UNIFIED_AUDIT_SYSTEMLOG init parameter specifies whether a piece of unified audit records will be written to the SYSLOG utility (on UNIX platforms) or to the Windows Event Viewer (on Windows). In a CDB, this parameter is a per-PDB static init parameter.