Oracle OpenWorld大会上宣布了oracle 11g已经发布了 beta，11g已经离我们越来越近了。

Oracle 11g新特性，原文地址：

http://www.dba-oracle.com/oracle11g/oracle_11g_new_features.htm

At Oracle Openworld 2006, Oracle announced some exciting new features of Oracle 11g, and they promise 482 specific new Oracle11g features:

• Oracle 11g parallel upgrades - Oracle 11g promises to have a rolling upgrade features whereby RAC database can be upgraded without any downtime. Ellison first promised this feature in 2002, and it is a very challenging and complex 11g new feature.

• Data Guard supports "Flashback Standby".
• OEM Easy de-install - This will uninstall both successful and unsuccessful Oracle installs.
• Interfaces to Applications - This note says "Oracle says that extending Enterprise Manager's capabilities are part of the firm's promise to seamlessly integrate the spoils of its many acquisitions -- including the purchases of Siebel Systems and PeopleSoft Corp. -- into a single platform."

• Oracle 11g audit vault - Oracle Audit Vault is a new feature that will provide a solution to help customers address the most difficult security problems remaining today, protecting against insider threat and meeting regulatory compliance requirements.

• New Trigger features - A new type of "compound" trigger will have sections for BEFORE, ROW and AFTER processing, very helpful for avoiding errors, and maintaining states between each section.

• Disabled state - Another 11g new feature is a "disabled" state for PL/SQL (as opposed to "enabled" and "invalid" in dba_objects).

• Partitioning - partitioning by logical object and automated partition creation.

• PHP - Improved PHP driver for Oracle.

• Database repair wizard - A GUI to guide beginners through the steps to diagnose and repair Oracle issues.

• LOB's - New high-performance LOB features.

• Compilers - Improved native Java & PL/SQL compilers.

• Hot patching - Zero downtime patch application.

• Standby snapshot - For the purpose of regression testing.

• Quick Fault Resolution - Automatic capture of diagnostics (dumps) for a fault.

OEM Oracle 11g new features:

• Grid provisioning - Oracle 11g OEM has have easy server blade installs where a binary footprint is tar'ed to the server blade and configured, without a cumbersome install process.

• OEM Easy de-install - This will uninstall both successful and unsuccessful Oracle installs.

• Better OEM Grid tools - Another new Oracle11g feature may be improved RAC and Grid monitoring, especially on the cache fusion interconnect.

• Interfaces to Applications - This note says "Oracle says that extending Enterprise Manager's capabilities are part of the firm's promise to seamlessly integrate the spoils of its many acquisitions -- including the purchases of Siebel Systems and PeopleSoft Corp. -- into a single platform."

Oracle 11g SQL and PL/SQL New Features

• The /*+result_cache*/ SQL hint - This suggests that the result data will be cached in the data buffers, and not the intermediate data blocks that were accessed to obtain the query results. You can cache both SQL and PL/SQL results for super-fast subsequent retrieval.

• PL/SQL "continue" keyword - This will allow a C-Like continue in a loop, to bypass any "else" Boolean conditions. A nasty PL/SQL GOTO is no longer required to exit a Boolean within a loop.

• Improved sequence management - A new features of Oracle 11g will bypass DML (sequence.nextval) and allow normal assignments on sequence values.

• A "super" PL/SQL keyword - This is used with OO Oracle when instantiating a derivative type (overloading), to refer to the superclass from whence the class was derived.

• Improved invalidation mechanism - A new 11g features will be fine grained dependency tracking, reducing the number of objects which become invalid as a result of DDL.

Lewis Cunningham notes these PL/SQL 11g new features:

• Fast DML triggers - DML triggers are up to 25% faster. This especially impacts row level triggers doing updates against other tables (think Audit trigger).

• Fine Grained Dependency Tracking (FGDT). This means that when you add a column to a table, or a cursor to a package spec, you don't invalidate objects that are dependant on them. Sweet!

• Easy PL/SQL compiling - Native Compilation no longer requires a C compiler to compile your PL/SQL. Your code goes directly to a shared library.

• New Data Type: simple_integer. Always NOT NULL, wraps instead of overflows and is faster than PLS_INTEGER.

• Intra-unit inlining. In C, you can write a macro that gets inlined when called. Now any stored procedure is eligible for inlining if Oracle thinks it will improve performance. No change to your code is required. Now you have no reason for not making everything a subroutine!

• Dynamic SQL. DBMS_SQL is here to stay. It's faster and is being enhanced. DBMS_SQL and NDS can now accept CLOBs (no more 32k limit on NDS). A ref cursor can become a DBMS_SQL cursor and vice versa. DBMS_SQL now supprts user defined types and bulk operations.

• FGAC for UTL_SMTP, UTL_TCP and UTL_HTTP. You can define security on ports and URLs.

• Read only tables

• Specify Trigger firing order.

• Compiler warning for a "when others" with no raise.

• Named notation when calling a stored procedure from SQL.

Dr. Hall notes these new 11g features:

11g new features in Fault Management:

• Automatic Diagnostic Repository (ADR) - When critical errors are detected, they automatically create an 搃ncident? Information relating to the incident is automatically captured, the DBA is notified and certain health checks are run automatically. This information can be packaged to be sent to Oracle support (see following).
  
• Incident Packaging Service (IPS) - This wraps up all information about an incident, requests further tests and information if necessary, and allows you to send the whole package to Oracle Support.
  
• Feature Based Patching - All one-off patches will be classified as to which feature they affect. This allows you to easily identify which patches are necessary for the features you are using. EM will allow you to subscribe to a feature based patching service, so EM automatically scans for available patches for the features you are using.

11g new features in Performance and Resource Management:

• Automatic SQL Tuning - The 10g automatic tuning advisor makes tuning suggestions in the form of SQL profiles that will improve performance. You can tell 11g to automatically apply SQL profiles for statements where the suggested profile give 3-times better performance that the existing statement. The performance comparisons are done by a new administrative task during a user-specified maintenance window.
  
• Access Advisor - The 11g Access Advisor gives partitioning advice, including advice on the new interval partitioning. Interval partitioning is an automated version of range partitioning, where new equally-sized partitions are automatically created when needed. Both range and interval partitions can exist for a single table, and range partitioned tables can be converted to interval partitioned tables.
  
• Automatic Memory Tuning - Automatic PGA tuning was introduced in Oracle 9i. Automatic SGA tuning was introduced in Oracle 10g. In 11g, all memory can be tuned automatically by setting one parameter. You literally tell Oracle how much memory it has and it determines how much to use for PGA, SGA and OS Processes. Maximum and minimum thresholds can be set.
  
• Resource Manager - The 11g Resource Manager can manage I/O, not just CPU. You can set the priority associated with specific files, file types or ASM disk groups.
  
• ADDM - The ADDM in 11g can give advice on the whole RAC (database level), not just at the instance level. Directives have been added to ADDM so it can ignore issues you are not concerned about. For example, if you know you need more memory and are sick of being told it, you can ask ADDM not to report those messages anymore.
  
• AWR Baselines - The AWR baselines of 10g have been extended to allow automatic creation of baselines for use in other features. A rolling week baseline is created by default.
  
• Adaptive Metric Baselines - Notification thresholds in 10g were based on a fixed point. In 11g, notification thresholds can be associated with a baseline, so the notification thresholds vary throughout the day in line with the baseline.

Laurent Schneider notes these Oracle 11g RAC performance enhancements:

• Server side connection pooling. An additional layer to the shared server, to enable faster [actually to bypass] session creation.

• Securefiles. This is a good one. It is a huge improvement to BLOB. Faster, with compression, encryption.

• Partition interval. This is a marvelous one ! You can now partition by date, one partition per month for example, with automatic partition creation.

• Rman backup can bypass undo. Undo tablespaces are getting huge, but contain lots of useless information. Now rman can bypass those types of tablespace. Great for exporting a tablespace from backup.

• Capture/replay workload. Sounds appealing. You can capture the workload in prod and apply it in development.

Mark Rittman also noted these Oracle 11g new feature announcements:

• The features in 11g focused on scalability and performance can be grouped into four areas: Scalable execution, scalable storage, scalable availability and scalable management.

• Scalable execution consists of a number of features, the first of which is query results caching; this feature automatically caches the results of an SQL query as opposed to the data blocks normally cached by the buffer cache, and works both client (OCI) and server side - this was described as "buffer cache taken to the next level". The DBA sets the size of the results cache and turns the feature on at a table level with the command "alter table DEPT cache results", the per-process cache is shared across multiple session and at the client level, is available with all 11g OCI-based clients.

• The next scalable execution feature is automatic creation of "native" PL/SQL and Java code, with just one parameter for each type with an "on/off" value. This apparently provides a 100% performance boost for pure PL/SQL and Java code, and a 10%-30% boost for code containing SQL.

• Server-side connection pooling allows multiple Oracle clients to share a server-side pool of sessions (USERIDs must match). Clients can connect and disconnect (think PHP applications) at will without the cost of creating a new server session - shared server removes the process creation cost but not the session creation cost.

• Order of magnitude faster optimizer stats creation

• Optimized cache fusion protocols - moves on from the general cache fusion protocols in 10g to deal with specific scenarios where the protocols could be further optimized
  Segment compression now works for all DML, not just direct-path loads, so you can create tables compressed and use them for regular OLTP work. Also supports column add/drop.

• Oracle SecureFiles - replacement for LOBs that are faster than Unix files to read/write. Lots of potential benefit for OLAP analytic workspaces, as the LOBs used to hold AWs have historically been slower to write to than the old Express .db files.

• Interval partitioning, a partitioning scheme that automatically creates time-based partitions as new data is added.

• Virtual columns, columns that are actually functions ("create table t1 (c1 number, c2 number, c3 as (c1+c2) virtual"), and similarly, virtual indexes that are based on functions
  REF partitioning, allowing you to partition a table based on the partition scheme of another. Allows you to partition an order_items table based off of the order_date column in an orders table.

• "Fully Automatic SQL Tuning", ADDM for RAC, Streams Performance Advisor, Partitioning Advisor