Oracle Database 12c 1z0-062 Reddit Questions

Interesting behavior in 12.1.0.1 DB of creating an undo tablespace in a PDB. With the new Multitenant architecture the undo tablespace resides at the CDB level and PDBs all share the same UNDO tablespace.

When the current container is a PDB, an attempt to create an undo tablespace fails without returning an error.

Note:

* Oracle 12c now provides the ability to index a subset of partitions and to exclude the others.

Local and global indexes can now be created on a subset of the partitions of a table. Partial Global indexes provide more flexibility in index creation for partitioned tables. For example, index segments can be omitted for the most recent partitions to ensure maximum data ingest rates without impacting the overall data model and access for the partitioned object.

Partial Global Indexes save space and improve performance during loads and queries. This feature supports global indexes that include or index a certain subset of table partitions or subpartitions, and exclude the others. This operation is supported using a default table indexing property. When a table is created or altered, a default indexing property can be specified for the table or its partitions.

About Startup Dependencies

Oracle Restart ensures that Oracle components are started in the proper order, in accordance with component dependencies. For example, if database files are stored in Oracle ASM disk groups, then before starting the database instance, Oracle Restart ensures that the Oracle ASM instance is started and the required disk groups are mounted. Likewise, if a component must be shut down, Oracle Restart ensures that dependent components are cleanly shut down first.

Oracle Restart also manages the weak dependency between database instances and the Oracle Net listener (the listener): When a database instance is started, Oracle Restart attempts to start the listener. If the listener startup fails, then the database is still started. If the listener later fails, Oracle Restart does not shut down and restart any database instances.

* Evolving SQL Plan Baselines

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2. Create the evolve task by using the DBMS_SPM.CREATE_EVOLVE_TASK function.

This function creates an advisor task to prepare the plan evolution of one or more plans for a specified SQL statement. The input parameters can be a SQL handle, plan name or a list of plan names, time limit, task name, and description.

1. Set the evolve task parameters.

SET_EVOLVE_TASK_PARAMETER

This function updates the value of an evolve task parameter. In this release, the only valid parameter is TIME_LIMIT.

4. Execute the evolve task by using the DBMS_SPM.EXECUTE_EVOLVE_TASK function.

This function executes an evolution task. The input parameters can be the task name, execution name, and execution description. If not specified, the advisor generates the name, which is returned by the function.

3: IMPLEMENT_EVOLVE_TASK

This function implements all recommendations for an evolve task. Essentially, this function is equivalent to using ACCEPT_SQL_PLAN_BASELINE for all recommended plans. Input parameters include task name, plan name, owner name, and execution name.

5. Report the task outcome by using the DBMS_SPM_EVOLVE_TASK function.

This function displays the results of an evolve task as a CLOB. Input parameters include the task name and section of the report to include.

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