Wednesday, July 2, 2008

What do all options in V$OPTION mean?

Since the introduction of Oracle8i a number of new parameters have been introduced into the V$OPTION table.


PARAMETER

Description

Advanced replication

This feature extends the capabilities of basic readonly replication by allowing applications to update table replicas throughout a replicated system.

Application Role

DBA_APPLICATION_ROLES describes all the roles that have authentication policy functions defined.

Backup Encryption

RMAN encryption. Ee.

Bit-mapped indexes

ee.

In a bitmap index, a bitmap for each key value is used, instead of a list of rowids. Each bit in the bitmap corresponds to a possible rowid, and if the bit is set, it means that the row with the corresponding rowid contains the value. If the number of different key values is small, bitmap indexes are very space efficient.

Block Change Tracking

ee. RMAN.

Block change tracking causes the changed database blocks to be flagged in a special file. To enable block change tracking: ALTER DATABASE ENABLE BLOCK CHANGE TRACKING USING FILE '/oracle/admin/SMILEY/bct.dbf'. Now any time a block is changed in the database, the fact is recorded in this special file. During incremental backup, RMAN checks this file to see which blocks need to be backed up instead of checking all the blocks of a data file. It dramatically reduces CPU cycles and speeds up incremental backup in the process.

Block Media Recovery

Block media recovery is a technique for restoring and recovering an individual corrupt datablock or set of datablocks within a datafile.

Change Data Capture

Change data capture (CDC) is a set of software design patterns used to determine the data that has changed in a database so that action can be taken using the changed data.

Coalesce Index

The COALESCE option was introduced as a less resource-intensive technique to regain free space in an index without having to rebuild it completely.

Connection multiplexing

MTS enables connection multiplexing with the connection manager. This allows multiple client connections to share a single connection from the connection manager to the database.

Connection pooling

MTS enables connection pooling where clients share connection slots in a pool on the server side by temporarily releasing client connections when connections are idle.

Data Mining

Oracle Data Mining (ODM) - an option to Oracle Database 10g Enterprise Edition - enables you to produce actionable predictive information and build integrated business intelligence applications. Data mining functionality embedded in Oracle Database 10g can find patterns and insights hidden in data.

Data Mining Scoring Engine

Some data-mining enabled applications have models that are developed on one system and then deployed to other (production) systems. Production applications often need only to apply models built elsewhere. The Oracle Data Mining Scoring Engine supports scoring data (applying models) using models created elsewhere.

The Scoring Engine allows customers to limit the Oracle Data Mining (ODM) functionality available within their scoring applications to ensure that compute-intensive operations such as model building are not performed on systems where Scoring Engine is installed.

Database queuing

This option integrates a message queueing system with the database. This allows users to store messages into queues for deferred retrieval and processing by the Oracle Server. This functionality may be accesses by a PL/SQL interface.

Database resource manager

Resource management decision has previously been done by the operating system. This gives rise to problems because there was no way of indicating to the OS,

database tasks of varying importance, also when the number of servers is high, there is excessive overhead due to OS context switching between database servers.

Duplexed backups

Recovery Manager can now create up to four concurrent copies of each backup piece. This feature is particularly useful for archivelog backups. If a data file backup is bad, an earlier backup of the same data file can usually still be used for recovery, but if an archivelog backup is bad, then no recovery beyond the point in time when that log was created is possible. Because archivelogs are critical to recovery, it is often required that archivelogs be backed up twice

before being deleted from disk.

Enterprise User Security

Enterprise User Security, an Oracle Database Enterprise Edition feature, combined with Oracle Identity Management, centrally manages database users and authorizations in one central place.

Export transportable tablespaces

The transportable tablespace feature enables you to move a set of tablespaces from one Oracle database to another.

Fast-Start Fault Recovery

To allow the database to quickly recover from system faults and minimize the impact on users, fast-start fault recovery has been introduced. It consists of

the components Fast-Start Checkpointing, Fast-Start On-Demand Rollback and Fast-Start Parallel Rollback.

File Mapping

The Oracle File Mapping feature provides a mechanism to illustrate a complete mapping of a file, through the intermediate layers of the IO cloud, down to the actual physical devices.

Fine-grained Auditing

Fine-grained auditing allows the monitoring of data access based on content.

Fine-grained access control

This provides the capability to define table- or view-based security policies. Attaching security policies to tables or views, rather than to applications, provides greater security, simplicity, and flexibility.

Flashback Database

Only available in ee, not se.

Flashback Table

Incremental backup and recovery

An incremental backup reads the entire file and then backs up only those data blocks that have changed since a previous backup. Oracle allows you to create and restore incremental backups of datafiles, tablespaces, or the whole database.

Instead-of triggers

INSTEAD OF triggers provide a transparent way of modifying views that cannot be modified directly through SQL DML statements (INSERT, UPDATE, and DELETE). These triggers are called INSTEAD OF triggers because, unlike other types of triggers, Oracle fires the trigger instead of executing the triggering statement. The trigger performs update, insert, or delete operations directly on the underlying tables.

Java

There are currently two methods for accessing Oracle data from Java programs: an Oracle-provided JDBC driver integrated with Oracle's object types, and JSQL for embedding SQL statements into Java code.

Join index

A join index is an index on one table that involves columns of one or more different tables through a join.

Managed Standby

When operating in this mode, you can automate archiving to either a local or remote host. Oracle keeps the standby database synchronized with the primary database by waiting for archived logs from the primary and then automatically applying them to the standby. This feature eliminates the need for you to interactively provide the recovery process with the filenames of the archived logs.

Materialized view rewrite

A materialized view is a stored summary containing precomputed results. Materialized views allow for significantly faster data warehouse query processing. With the Oracle8i summary management feature, the Oracle database server automatically rewrites queries to use the summary data, rather than retrieving data from detail tables by doing expensive joins and aggregate operations. This query rewrite facility is totally transparent to the application, which is not aware of the existence of the materialized view.

Materialized view warehouse refresh

A materialized view is maintained by a refresh process. The refresh process can be done automatically when a commit is done on a detail table, or it can be

controlled manually by the DBA. A refresh is specified as complete or incremental. A complete refresh truncates existing data, then repopulates the summary with new data from the detail tables. An incremental refresh updates only changed data.

OLAP

OLAP Window Functions

Objects

Objects may be used to create a user-defined object type, where the user may define the structure of the data and the ways of operating on it.

Online Index Build

Indexes may be built and rebuilt without locking the table during the operation.

Online Redefinition

Oracle Data Guard

Oracle Label Security

Parallel backup and recovery

Recovery Manager may parallelize its operations, establishing multiple logon sessions and conducting multiple backup sets or file copies in parallel.

Concurrent backup sets or image copies must operate on disjoint sets of database files.

Parallel execution

When Oracle is not parallelizing the execution of SQL statements, each SQL statement is executed sequentially by a single process. With parallel execution, however, multiple processes work together simultaneously to execute a single SQL statement. By dividing the work necessary to execute a statement among multiple processes, Oracle can execute the statement more quickly than if only a single process executed it.

Parallel load

Parallel specifies whether direct loads can operate in multiple concurrent sessions to load data into the same table

Partitioning

A partitioned table or index is divided into a number of pieces all having the same logical attributes. The individual partitions are stored in separate segments and may also be stored in separate tablespaces.

Plan Stability

This prevents certain database environment changes from affecting the performance characteristics of your applications. Such changes include changes to the

optimizer mode settings and changes to parameters affecting the sizes of memory structures such as SORT_AREA_SIZE, and BITMAP_MERGE_AREA_SIZE.

Point-in-time tablespace recovery

Tablespace Point-In-Time Recovery (TSPITR) enables you to quickly recover one or more tablespaces to a point-in-time that is different from that of the rest of the database.

Proxy authentication/authorization

Real Application Clusters

Sample Scan

A sample table scan retrieves a random sample of data from a table. This access method is used when the statement's FROM clause includes the SAMPLE option or

the SAMPLE BLOCK option. Oracle reads a specified percentage of rows/blocks in the table and examines each of them to determine whether it satisfies the statement's WHERE clause.

Spatial

Oracle Spatial Cartridge is an integrated set of functions and procedures that enables spatial data to be stored, accessed, and analyzed quickly and efficiently.

Streams Capture

Table compression

Transparent Application Failover

Should a node in the Oracle Parallel Server fail, transparent application failover will migrate the connections and automatically re-establish the sessions on another node. The applications will continue to run, and you may be unaware of the failure.

Transparent Data Encryption

Trial Recovery

Unused Block Compression

Visual Information Retrieval

This is an extension to Oracle8i Enterprise Edition that provides image storage, content-based retrieval, and format conversion capabilities through an object type. This product supports image storage using binary large objects (BLOBs) and references to image data residing externally in BFILEs or URLs.





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