Oracle 1z0-060 Dumps

Multipartition maintenance enables adding, dropping, truncate, merge, split operations on multiple partitions.

A: Merge Multiple Partitions:

The new “ALTER TABLE … MERGE PARTITIONS ” help merge multiple partitions or subpartitions with a single statement. When merging multiple partitions, local and global index operations and semantics for inheritance of unspecified physical attributes are the same for merging two partitions.

B: Drop Multiple Partitions:

The new “ALTER TABLE … DROP PARTITIONS ” help drop multiple partitions or subpartitions with a single statement.

Example:

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SQL> ALTER TABLE Tab_tst1 DROP PARTITIONS

Tab_tst1_PART5, Tab_tst1_PART6, Tab_tst1_PART7;

Table altered

SQL>

Restrictions:

* You can include the CONTAINER clause in several SQL statements, such as the CREATE USER, ALTER USER, CREATE ROLE, GRANT, REVOKE, and ALTER SYSTEM statements.

* * CREATE ROLE with CONTAINER (optional) clause

/ CONTAINER = ALL

Creates a common role.

/ CONTAINER = CURRENT

Creates a local role in the current PDB.

You can use the SQL Performance Analyzer to analyze the SQL performance impact of any type of system change. Examples of common system changes include:

References:

* To implement your ILM strategy, you can use Heat Map in Oracle Database to track data access and modification.

Heat Map provides data access tracking at the segment-level and data modification tracking at the segment and row level.

* To implement your ILM strategy, you can use Heat Map in Oracle Database to track data access and modification. You can also use Automatic Data Optimization (ADO) to automate the compression and movement of data between different tiers of storage within the database.

Manually Sized SGA Components that Use SGA_TARGET Space

SGA Component, Initialization Parameter

/ The log buffer

LOG_BUFFER

/ The keep and recycle buffer caches

DB_KEEP_CACHE_SIZE

DB_RECYCLE_CACHE_SIZE

/ Nonstandard block size buffer caches

DB_nK_CACHE_SIZE

Note:

* In addition to setting SGA_TARGET to a nonzero value, you must set to zero all initialization parameters listed in the table below to enable full automatic tuning of the automatically sized SGA components.

* Table, Automatically Sized SGA Components and Corresponding Parameters

If you run multiple AUDIT statements on the same unified audit policy but specify different EXCEPT users, then Oracle Database uses the last exception user list, not any of the users from the preceding lists. This means the effect of the earlier AUDIT POLICY ... EXCEPT statements are overridden by the latest AUDIT POLICY ... EXCEPT statement.

Note:

* The ORA_DATABASE_PARAMETER policy audits commonly used Oracle Database parameter settings. By default, this policy is not enabled.

* You can use the keyword ALL to audit all actions. The following example shows how to audit all actions on the HR.EMPLOYEES table, except actions by user pmulligan.

Example Auditing All Actions on a Table

CREATE AUDIT POLICY all_actions_on_hr_emp_pol

ACTIONS ALL ON HR.EMPLOYEES;

AUDIT POLICY all_actions_on_hr_emp_pol EXCEPT pmulligan;

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:

* SQL*Loader is invoked when you specify the sqlldr command and, optionally, parameters that establish session characteristics.

Execute the DBMS_XDB_CONFIG.SETHTTPSPORT procedure.

References:

About Altering the Default Full Data Redaction Value

You can alter the default displayed values for full Data Redaction polices. By default, 0 is the redacted value when Oracle Database performs full redaction (DBMS_REDACT.FULL) on a column of the NUMBER data type. If you want to change it to another value (for example, 7), then you can run the DBMS_REDACT.UPDATE_FULL_REDACTION_VALUES procedure to modify this value. The modification applies to all of the Data Redaction policies in the current database instance. After you modify a value, you must restart the database for it to take effect.

Note:

* The DBMS_REDACT package provides an interface to Oracle Data Redaction, which enables you to mask (redact) data that is returned from queries issued by low-privileged users or an application.

* UPDATE_FULL_REDACTION_VALUES Procedure

This procedure modifies the default displayed values for a Data Redaction policy for full redaction.

* After you create the Data Redaction policy, it is automatically enabled and ready to redact data.

* Oracle Data Redaction enables you to mask (redact) data that is returned from queries issued by low-privileged users or applications. You can redact column data by using one of the following methods:

/ Full redaction.

/ Partial redaction.

/ Regular expressions.

/ Random redaction.

/ No redaction.

1. Shut down the database.

2. Restart the database in UPGRADE mode.

3. Change the setting of MAX_STRING_SIZE to EXTENDED.

4. Run the rdbms/admin/utl32k.sql script. You must be connected AS SYSDBA to run the script.

5. Restart the database in NORMAL mode.

References:

* SHUTDOWN [ABORT | IMMEDIATE | NORMAL | TRANSACTIONAL [LOCAL]]

Shuts down a currently running Oracle Database instance, optionally closing and dismounting a database. If the current database is a pluggable database, only the pluggable database is closed. The consolidated instance continues to run.

Shutdown commands that wait for current calls to complete or users to disconnect such as SHUTDOWN NORMAL and SHUTDOWN TRANSACTIONAL have a time limit that the SHUTDOWN command will wait. If all events blocking the shutdown have not occurred within the time limit, the shutdown command cancels with the following message:

ORA-01013: user requested cancel of current operation

* If logged into a CDB, shutdown closes the CDB instance.

To shutdown a CDB or non CDB, you must be connected to the CDB or non CDB instance that you want to close, and then enter

SHUTDOWN

Database closed.

Database dismounted.

Oracle instance shut down.

To shutdown a PDB, you must log into the PDB to issue the SHUTDOWN command.

SHUTDOWN

Pluggable Database closed.

Note:

* Prerequisites for PDB Shutdown

When the current container is a pluggable database (PDB), the SHUTDOWN command can only be used if:

The current user has SYSDBA, SYSOPER, SYSBACKUP, or SYSDG system privilege.

The privilege is either commonly granted or locally granted in the PDB.

The current user exercises the privilege using AS SYSDBA, AS SYSOPER, AS SYSBACKUP, or AS SYSDG at connect time.

To close a PDB, the PDB must be open.

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.

References:

* In bind variable peeking (also known as bind peeking), the optimizer looks at the value in a bind variable when the database performs a hard parse of a statement.

When a query uses literals, the optimizer can use the literal values to find the best plan. However, when a query uses bind variables, the optimizer must select the best plan without the presence of literals in the SQL text. This task can be extremely difficult. By peeking at bind values the optimizer can determine the selectivity of a WHERE clause condition as if literals had been used, thereby improving the plan.

C: Oracle 11g/12g uses Adaptive Cursor Sharing to solve this problem by allowing the server to compare the effectiveness of execution plans between executions with different bind variable values. If it notices suboptimal plans, it allows certain bind variable values, or ranges of values, to use alternate execution plans for the same statement. This functionality requires no additional configuration.

You can choose to archive redo logs to a single destination or to multiple destinations.

Destinations can be local—within the local file system or an Oracle Automatic Storage Management (Oracle ASM) disk group—or remote (on a standby database). When you archive to multiple destinations, a copy of each filled redo log file is written to each destination. These redundant copies help ensure that archived logs are always available in the event of a failure at one of the destinations.

To archive to only a single destination, specify that destination using the LOG_ARCHIVE_DEST and LOG_ARCHIVE_DUPLEX_DEST initialization parameters.

ARCHIVE_DEST initialization parameter. To archive to multiple destinations, you can choose to archive to two or more locations using the LOG_ARCHIVE_DEST_n initialization parameters, or to archive only to a primary and secondary destination using the LOG_ARCHIVE_DEST and LOG_ARCHIVE_DUPLEX_DEST initialization parameters.

A (not B, not E): The CREATE DATABASE ... ENABLE PLUGGABLE DATABASE SQL statement creates a new CDB. If you do not specify the ENABLE PLUGGABLE DATABASE clause, then the newly created database is a non-CDB and can never contain PDBs.

D: You can create a PDB by plugging in a Non-CDB as a PDB.

The following graphic depicts the options for creating a PDB:

A: PGA itself is subdivided. The UGA (User Global Area) contains session state information, including stuff like package-level variables, cursor state, etc. Note that, with shared server, the UGA is in the SGA. It has to be, because shared server means that the session state needs to be accessible to all server processes, as any one of them could be assigned a particular session. However, with dedicated server (which likely what you're using), the UGA is allocated in the PGA.

C: The Location of a private SQL area depends on the type of connection established for a session. If a session is connected through a dedicated server, private SQL areas are located in the server process’ PGA. However, if a session is connected through a shared server, part of the private SQL area is kept in the SGA.

Note:

* System global area (SGA)

The SGA is a group of shared memory structures, known as SGA components, that contain data and control information for one Oracle Database instance. The SGA is shared by all server and background processes. Examples of data stored in the SGA include cached data blocks and shared SQL areas.

* Program global area (PGA)

A PGA is a memory region that contains data and control information for a server process. It is nonshared memory created by Oracle Database when a server process is started. Access to the PGA is exclusive to the server process. There is one PGA for each server process. Background processes also allocate their own PGAs. The total memory used by all individual PGAs is known as the total instance PGA memory, and the collection of individual PGAs is referred to as the total instance PGA, or just instance PGA. You use database initialization parameters to set the size of the instance PGA, not individual PGAs.

D: DB_FILE_MULTIBLOCK_READ_COUNT is one of the parameters you can use to minimize I/O during table scans. It specifies the maximum number of blocks read in one I/O operation during a sequential scan. The total number of I/Os needed to perform a full table scan depends on such factors as the size of the table, the multiblock read count, and whether parallel execution is being utilized for the operation.