Oracle7 TM Release 7.3

Oracle ® Universal Server®
Oracle7 Release 7.3 is the relational database component of Oracle Universal Server, the first in a new generation of information management systems capable of handling all types of information for all types of application at any scale. Oracle Universal Server is a family of Oracle server products that provide the most scalable and high-performance deployment platform for business applications in the industry today - heralding a new era in comprehensive data management. With complete Web support, messaging, and multimedia data support, Oracle Universal Server is fundamentally linked to the overall transition in the computing industry toward network-centric computing and the information explosion, where any application can access any data at any scale.

Product Summary
Oracle7 Release 7.3 provides efficient, reliable, secure data management for applications ranging from mission-critical online transaction processing applications to query-intensive data warehouses. Release 7.3 incorporates significant improvements in performance, scalability, and functionality aimed primarily at providing support for data warehousing and OLTP applications. In addition, this release includes functional enhancements in selected areas that improve application developer productivity, advance Oracle7's industry-leading distributed systems support, and improve the overall manageability of the server with Oracle Enterprise Manager. TM

Maintenance Release
Oracle7 Release 7.3, the most recent maintenance release of the Oracle7 Server, builds on the reliability and functionality engineered into earlier releases of Oracle7. Release 7.3 is the standard maintenance/upgrade path from release 7.2. New features in Release 7.3 can be disabled via a startup parameter, allowing for safe installation into existing production environments. Release 7.3 maintains 100-percent compatibility with Releases 7.0, 7.1, and 7.2-no application changes or data reorganization are required.

Enterprise Data Warehousing
Oracle7 provides high performance, scalability, and high availability within an integrated, dynamic architecture for data warehouse and decision support applications. Release 7.3 advances the capabilities of the Oracle7 Server with major improvements in the performance and scalability of common data warehouse and decision support operations.

Parallel Execution Enhancements
Release 7.3 supports parallel execution of UNION and UNION ALL operations commonly used in decision support applications to assemble result sets from multiple underlying tables. Other new features include parallel execution of NOT IN conditions and improved parallel execution of GROUP BY operations.

Parallel-Aware Query Optimization
The cost-based optimizer in Release 7.3 incorporates parallel execution consider-ations as a fundamental component in arriving at query execution plans. The optimizer chooses intelligent heuristic defaults for parallelism based on the number of available processors and the disk devices that store table data. Access path choices - table scan vs. index access, for example - take into account the degree of parallelism available, resulting in plans that are optimized for parallel execution.

Optimizer Enhancements
The cost-based optimizer utilizes data value histograms to obtain accurate estimates of the distribution of column data. The use of histograms provides improved selectivity estimates in the presence of data skew, resulting in optimal execution plans with non-uniform data distributions. Release 7.3 includes further performance improvements in the processing of star queries commonly used in decision support applications. The optimizer also incorporates numerous other enhancements to achieve significant gains in the processing of operations such as "anti-joins" involving the NOT IN condition, and the evaluation of OR condi-tions.

Partition Views
Release 7.3 delivers the functionality to support partition views. A partition view allows a table, typically one with a large amount of data, to be broken into multiple smaller tables (i.e. partitions) and then presented to applications as a single object through the use of a UNION ALL view. Partition views of large tables deliver significant improvements in availability, administration, and performance. A partitioned table enables data management operations such as data loads, index creation, and data purges to be done at the partition level, rather than on the entire table, resulting in significantly reduced times for these operations. Furthermore, since the partitions are independent of each other, the navailability of a partition of data does not affect access to the rest of the data in the partition view.

Release 7.3 incorporates the intelligence to explicitly recognize partition views and optimize query execution in several ways. Partition elimination will occur when selection criteria eliminates all rows of a partitioned table, thus making it unnecessary to access that partition and improving query performance dramatically. The optimizer also has the ability to execute different query execution plans for each underlying table of the partition view.

Bitmapped Indexes
Release 7.3 incorporates bitmapped indexing as an integrated server capability, delivering dramatic performance benefits to decision support applications, without any compromises in server functionality. Bitmapped indexes coexist with and complement other available indexing schemes including standard B-tree indexes, clustered tables, and hash clusters. Bitmapped indexes are ideally suited for low-cardinality column data - columns that have a relatively small number of possible values - and can deliver very dramatic performance gains for ad-hoc queries involving logical operations on these columns. Oracle7 utilizes a patented data compression technology and several unique optimizations to deliver efficient storage of bitmapped indexes and significant performance gains in query processing with these indexes.

Hash Joins
Release 7.3 introduces a new join algorithm, the hash join, that can deliver dramatic performance improvements over current join methods in many complex queries. Hash joins eliminate the need to perform sorts by using an in-memory hash table constructed at run-time. They are also ideally suited for scalable parallel execution. The cost-based optimizer in Release 7.3 incorporates the intelligence to choose the most appropriate join method based on the characteristics of the tables involved in a given query. In addition, application developers can explicitly specify the use of hash join through a new hint.

Asynchronous Read-Ahead for Table Scans
An asynchronous read-ahead mechanism for table scans is included in release 7.3, delivering performance improvements for queries involving large tables. Using this mechanism, additional data is synchronously retrieved from disk while the current set is being processed. This achieves an overlap between I/O and processing and delivers much higher throughput for all parallel query operations.

Exploitation of Data Locality
Release 7.3 improves the performance of parallel query execution on loosely coupled systems based on "shared-nothing" hardware architectures by exploiting the affinity of disks to individual processing nodes. Using the knowledge of data locality, the system optimally allocates work to query slaves located on nodes where the data resides and minimizes inter-node data movement, achieving substantial performance gains.

Space Management Improvements
Release 7.3 contains several improvements in space management to facilitate superior support for very large objects and better utilization of available space. The limit on the number of extents per object is removed, enabling easy creation and maintenance of very large tables and indexes. There are also new facilities available for releasing unused space from a table and coalescing contiguous free space on demand.

Improved Space Management for Sorts
Space management for sort operations is performed more efficiently using TEMPORARY tablespaces designated exclusively for sorts. This scheme effectively eliminates serialization of space management operations involved in the allocation and de-allocation of sort space. All operations that use sorts - including joins, index builds, ordering (ORDER BY), the computation of aggregates (GROUP BY), and the ANALYZE command to collect optimizer statistics - benefit from this improvement. The performance gains are especially significant in parallel server environments.

Improved EXPLAIN PLAN
The EXPLAIN PLAN facility now provides additional details on parallel query execution operations and more granular cost estimates to aid in SQL tuning.

Enterprise Transaction Processing
Release 7.3 incorporates numerous internal enhancements and selected new features that significantly improve the performance and scalability of on-line transaction processing (OLTP) applications and provide high availability for mission-critical applications.

Scalability Enhancements
Release 7.3 significantly advances Oracle7�s industry-leading scalability record on high-end multiprocessor systems. This release incorporates a number of internal changes that eliminate potential serialization points and provides major improvements in scalability and performance under heavy loads. Shared resources such as the buffer cache and the shared SQL cache are logically segmented into multiple sets, reducing contention on multiprocessor systems. Triggers are stored in compiled form, providing improved run-time performance. Release 7.3 also includes performance and scalability improvements for applications using industry-standard XA-compliant Transaction Processing (TP) monitors.

Parallel Server Enhancements
A new fine-grained locking mechanism enables the specification of parallel cache management locks for optimal performance. Using this facility, administrators can minimize the need for inter-instance communication and substantially reduce or even eliminate unneeded messages, known as "false pings," to achieve significant performance gains. A simple load balancing scheme available in SQL*Net ® Version 2.3 facilitates even distribution of incoming user connections across multiple parallel server instances. Release 7.3 also includes several internal improvements resulting in improved performance and scalability.

Improved Memory Management
Release 7.3 incorporates significant improvements in the management of shared memory resources, reducing memory usage and enabling better utilization of available memory. Most of these enhancements are internal algorithmic changes requiring minimal or no user-visible changes. These changes result in a substantial reduction in memory usage by PL/SQL TM stored procedures, functions, and packages. Applications that make extensive use of PL/SQL stored objects could achieve as much as 30- to 40-percent reductions in shared memory usage. Release 7.3 also delivers dramatic reductions in per-user and per-cursor memory usage, enabling improved support for large numbers of concurrent users.

Standby Database for High-Availability Applications
Release 7.3 provides a reliable and supported mechanism for implementing a standby database system to facilitate quick disaster recovery. The scheme uses a secondary system on duplicate hardware, maintained in a constant state of media recovery through the application of log files archived at the primary site. In the event of a primary system failure, the standby can be activated with minimal recovery, providing immediate system availability. There are new commands and internal verifications for operations involved in the creation and maintenance of the standby system, improving the reliability of the disaster recovery scheme.

Faster Instance Startup
Release 7.3 incorporates a deferred transaction recovery mechanism to facilitate quicker instance startup following a system crash. Rollback operations related to uncommitted transactions are performed in parallel after startup, providing earlier system availability.

Serializable Transactions
Release 7.3 extends Oracle's powerful read consistency model to support serializable transactions. Application developers can now specify a high degree of isolation between concurrently running transactions using the command SET TRANSACTION ISOLATION LEVEL SERIALIZABLE, as defined in SQL92. Serializable transactions see a fixed snapshot of the data, established as of the beginning of the transaction.

Enterprise Application Development
In conjunction with PL/SQL Release 2.3 and the Oracle Programmatic Interfaces, Release 7.3 introduces significant new functionality that improves the productivity of application developers and the performance of applications.

PL/SQL Enhancements
PL/SQL tables incorporate a number of significant enhancements. Tables of composite data types are supported, eliminating the need to use multiple "parallel" tables, resulting in simpler code. Common operations on tables such as FIRST, LAST, and EXISTS provide easy access to the table contents, improving usability.

Release 7.3 incorporates numerous enhancements including changes in dependency management between remote PL/SQL stored procedures and the storage of triggers in compiled form, resulting in improved run-time performance for PL/SQL applications. The limit on the size of PL/SQL stored objects is effectively doubled, enabling improved support for larger, complex PL/SQL applications. Release 7.3 contains a new utility that enables PL/SQL application developers to perform server-side file I/O operations and record application-specific messages, warnings or debug information in operating system files directly.

PL/SQL 2.3 enhances support for cursor variables, enabling PL/SQL applications to retrieve multi-row result sets from stored procedures.

Updatable Join Views
Release 7.3 allows unambiguous insert, update, and delete operations on views involving multi-table joins, providing additional flexibility and improved productivity in application development.

Multi-Threaded Client Applications
The Oracle Call Interface TM (OCI) and the Oracle precompilers provide support for multi-threaded client applications. All the client-side libraries are made thread-safe with Release 7.3. Oracle's implementation of thread safety allows for maximum concurrency in multi-threaded applications by making OCI code re-entrant and allowing multiple threads of a user program to make OCI calls without having any side effect from one thread to another. The principal benefits of this new feature is that multiple threads can use Oracle library calls with the same result as if they were executed serially and that the cursors to statements in a session are shareable serially.

OCI Enhancements
With Release 7.3, OCI supports the insert and update of LONG data in pieces, reducing memory requirements on the client side. OCI users can also simplify insert and fetch operations using arrays of structures in place of multiple arrays of scalars.

Enterprise Systems Management
With Release 7.3, Oracle continues its commitment to enterprise and workgroup systems management with Oracle Enterprise Manager, a new graphical systems management tool. As a scalable solution, Enterprise Manager simplifies administration and maximizes manageability across the entire Oracle7 product family. In addition, Release 7.3 includes new features in the server that provide improvements in availability and manageability.

Comprehensive Server Management
Oracle Enterprise Manager provides database and systems administrators with an intuitive graphical interface, an integrated management console, and applications which maintain consistently high levels of distributed performance and data integrity while dramatically reducing the number of hours administrators need to spend managing production environments. The open architecture of Oracle Enterprise Manager allows both third-party vendor and custom client applications to be integrated into Oracle's enterprise management platform, which gives DBAs the flexibility to tailor Oracle's management plat-form to best meet their specific needs.

Oracle Enterprise Manager, in addition to standard DBA utilities such as back-up, import, export, load, and recovery, supports various services which are designed to simplify system administration. For example, the job scheduling system allows administrators to schedule repetitive jobs at local and remote sites, such as backing up the database or running reports, making a "lights out" systems management operation possible. The event management system monitors specific events at local and remote sites and alerts the administrator when a problem is detected. The security service manages administrative privileges for the nodes and services in the system and, the service discovery system provides an up-to-date view of the nodes and services being managed.

Performance Tuning Tools
Oracle7 provides Oracle Trace TM and Oracle Expert TM to assist in collecting, analyzing, and configuring Oracle7 database and application code. These tools collect data on production systems and make recommendations that will optimize performance, greatly simplifying and reducing guess work sometimes associated with database performance tuning.

Oracle Trace is a flexible and powerful performance data collection tool, providing users with fine grained collection of performance statistics. Oracle Trace uses an efficient event-based mechanism to minimize the overhead associated with data collection.

Oracle Expert is a rule-based expert system for analyzing data collected using Oracle Trace. Oracle Expert aids in the automation of data analysis, and generates configuration and tuning recommendations based on the performance data. Recommendations, such as index creation and SGA memory size adjustments, are made based on preferences input, such as the hardware configuration at the database site. Script files are automatically generated to implement recommendations if they are accepted.

Faster Index Rebuilds
Release 7.3 introduces a new operation that uses an existing index, rather than the base table, as the data source for rebuilding an index. Since the indexed data is typically much smaller, use of this facility will substantially reduce the time for index rebuilds.

Faster Export
Release 7.3 offers a new fast-path DIRECT option to the EXPORT utility. This mode bypasses SQL processing to yield substantial improvements in the performance of table data extraction using EXPORT. Initial tests have shown a more than two-fold increase in performance.

Media Recovery Status
Release 7.3 provides status information on the progress of media recovery using new dynamic views. This information is externalized through new facilities in Oracle Enterprise Manager.

Faster Mirrored File Resilvering
A new server-mediated resilvering mechanism is available in Release 7.3 for correcting inconsistencies between the replicas of a mirrored data file. Resilvering by the operating system, due to absence of any content knowledge, is typically a very expensive operation. This feature provides the option of resilvering mediated by the Oracle7 server, using content knowledge to resolve inconsistencies at a finer granularity and to substantially reduce the time required to perform resilvering. Availability of this feature is platform-specific.

Improved Serviceability
Release 7.3 includes new facilities and improvements to existing tools, facilitating quicker and better diagnosis of problems. DBVERIFY, a new utility available with Release 7.3, performs validation of the physical structure of database files, providing administrators a convenient mechanism for validating backup files. While some of the new tools are available for customer use, most are intended for internal use by Oracle support personnel.

Enterprise Distributed Solutions
Release 7.3 includes management, performance, and functional improvements to Oracle7 Symmetric Replication, TM the industry's most advanced asynchronous distributed computing technology introduced with Oracle7 Release 7.1.

Improved Management
Oracle7 Replication Manager TM is a component of Oracle7 Enterprise Manager that enables your administrator to easily configure and operate replicated databases. Administrators can use the graphical user interface to select which database objects should be replicated, add replication sites, and determine how the replicated data should be propagated. Release 7.3 also includes a new utility that compares the contents of replicated copies to identify and optionally correct any divergence. Oracle7 Replication Manager provides flexibility and easy adminis-tration for even the most complicated replicated database systems.

Functional Enhancements
With Release 7.3, users can utilize synchronous propagation of changes between replicated tables, in addition to the asynchronous store-and-forward mechanism normally used. Depending on their business requirements, users can now choose between the two modes.

Improved Performance
The Oracle7 Symmetric Replication facility benefits directly from stored triggers and other PL/SQL run-time performance improvements. Other internal improvements and performance features add to these gains.

World Wide Web Integration
Release 7.3 includes the Oracle WebServer, TM which enables existing Oracle7 business applications to be fully integrated with World Wide Web technology and deployed in either a corporate network ("intranet") or the public Internet. The Oracle WebServer makes it possible for businesses to make data stored in Oracle7 databases available to users of the World Wide Web.

The Oracle WebServer enables stored procedures to be invoked by clients using Web Browsers to generate dynamic Web documents, so that Web pages are no longer limited to displaying information from static files. The components of the Oracle7 WebServer are the Oracle Web Listener, a high-performance HTTP server, and the Oracle Web Agent, the gateway to the Oracle7 Server.

Advanced Text Processing
The Oracle7 ConText Option enables Oracle7 to handle text with the same security, scalability, integrity, and intelligence as it manages structured data. Oracle7 provides an integrated database environment offering secure, reliable access to strategic text information in conjunction with structured data types, scalable to millions of documents and thousands of users.

The interface to ConText is standard SQL, so that familiar Oracle and third-party tools can combine structured data operations with intelligent text searches and text reductions. Text-enabled applications can be quickly developed, or existing systems can be easily enhanced to take advantage of advanced text capabilities. In Oracle7, this includes the retrieval, management, reduction, and classification of text in many languages and formats.

Spatial Data Management
The Oracle7 Spatial Data Option TM provides the ability to manage spatial information as an integrated function of the database. It enables spatial data to be efficiently stored, accessed, and manipulated in the database in the same manner as structured data. The Spatial Data Option functionality is a key component of any information system where location is an important part of the decision-making process.

Integrated Audio and Video
The Oracle Video Server TM is an end-to-end software solution that enables you to store, manage, and deliver full-motion, full-screen video, and high-fidelity audio to clients over a corporate network. It supports applications that incorporate rich multimedia data, developed using a variety of Oracle and third-party development tools.

The Video Server includes the Oracle Video Server, Oracle Video Client, and Oracle Media Net software to enable real-time delivery of video streams at varied bit rates in a distributed environment. The Oracle Video Client software includes support for Oracle Media Objects TM and Oracle Power Objects. TM Through the client programming interface, the Oracle Video Server also supports other applications that can embed OLE Custom Extensions (OCX).

Product Components

Server Components Systems Management PL/SQL and Programmatic Interfaces Networking

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