Author: biju.thomas

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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.
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Oracle Tidbits – June 2018 #oratidbit

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

#oratidbit #db18c A shared single client access name (Shared SCAN) enables the sharing of one set of SCAN virtual IPs (VIPs) and Listeners on one dedicated cluster in the data center with other clusters to avoid the deployment of one SCAN setup per cluster.
#oratidbit #db18c You can convert a conventional disk group (disk group created before Oracle ASM 18c) to an Oracle ASM flex disk group without using the restrictive mount (MOUNTED RESTRICTED) option.
#oratidbit #orachk #exachk Oracle Health Check Collections Manager by default purges collections that are older than three months.
#oratidbit #db18c You can drop a file group and its associated files (drop including content) using the CASCADE keyword with ALTER DISKGROUP … DROP FILEGROUP SQL statement.
#oratidbit #orachk #exachk The -failedchecks option to run only the checks that failed previously. After fixing the issues identified by orachk, you may generate another health check report to verify only the issues that failed before.
#oratidbit The Oracle ASM Intelligent Data Placement (IDP) feature has been deprecated since Oracle ASM 12c Release 2 (12.2) and desupport is planned in a future release.
#oratidbit Oracle #ORAchk supports Oracle Grid Infrastructure stand-alone checks where no database is installed. Use the option -nordbms.
#oratidbit #db18c The Data Pump Import DATA_OPTIONS parameter has a new CONTINUE_LOAD_ON_FORMAT_ERROR option. If Data Pump encounters a stream format error, it attempts to skip forward to find the start of the next row and continue loading data from that location.
#oratidbit #db18c The DATA_OPTIONS parameter of the DBMS_DATAPUMP.SET_PARAMETER procedure has a new option, KU$_DATAOPT_CONT_LOAD_ON_FMT_ERR, to continue loading data from the next row if it encounters stream format errors in the table data.
#oratidbit Use the ENCRYPTION_MODE=TRANSPARENT setting to transparently encrypt the data pump dump file set with the TDE master encryption key stored in the keystore. The keystore must be present and open at the target database during an import operation.
#oratidbit #db18c #SQLDev #ADWC SQL Developer 18.1 Data Import Wizard can load data from files in the Oracle Cloud (or local storage) to Autonomous Data Wareshouse Cloud using the DBMS_CLOUD API.
#oratidbit #SQLDev #ADWC SQL Developer Cloud Migrations wizard can migrate schemas, objects (tables), and data from an Amazon #Redshift database to Oracle Autonomous Data Warehouse Cloud.
#oratidbit #SQLDev SQL Developer provides interactive advisories in the code editor identifying code that is at risk of SQL injection. First-order injection is when user-specified data from function parameters is used in a dynamic SQL statement that can be exploited.
#oratidbit #sqlcl SET HISTORY BLACKLIST allows you to set the commands that should not be recorded in history. By default, the SHOW, HISTORY, CONNECT, and SET commands are not saved in history.
#oratidbit PL/SQL data type PLS_INTEGER has advantages over the NUMBER data type. Requires less storage and uses hardware arithmetic, so they are faster than NUMBER operations, which use library arithmetic.
#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 Init parameter CURSOR_INVALIDATION controls whether deferred or immediate cursor invalidation is used for DDL statements. Deferred invalidation spreads the recompilation workload over time. A cursor may run with a sub-optimal plan until recompiled.
#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.