Oracle 9i release 1. Administration. Database Outsourcing Experts

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1 Administration Default Temporary Tablespace The system will automatically allocate new users an appropriate temporary tablespace without you needing to specify it explicitly in the create user statement. This is achieved by specifying a pre-created temporary tablespace as default using a new extension of the create tablespace and alter tablespace commands. Automatic Undo Management In an effort to reduce administration overheads, it is now possible to have the system manage it s own rollback segments (now known as undo segments) by specifying the undo tablespace and undo management type in the parameter file. The system-managed undo tablespace is essentially a locally managed tablespace with space managed by a bitmap in the file header. Constraint Enhancements Enhancements to the using index clause of create table and alter table statements means you can specify the creation or use of a specific index when dealing with primary keys. You can also prevent indexes from being dropped when dropping constraints. Database Quiescence You place the database in a quiesced state in which only the SYS and SYSTEM users can perform transactions. This basically removes the need to stop the database and restart in restricted mode if you want to perform tasks that could interfere with normal usage. Database Suspend/Resume This feature allows you to suspend database activity by stopping I/O to all datafiles and queuing any further I/O requests. When ready, you can then resume database operations and the system will re-activate all pending I/O requests in the order they were queued. This is extremely useful for system backups that involve splitting mirrored disks. Datafile Management New feature allows for automatic management of datafiles when you issue tablespace commands. By specifying a directory location in the init.ora file (or by an alter system command), the system will automatically create and delete datafiles in that location as necessary. A new addition to the drop tablespace clause ( drop tablespace including contents and datafiles ) will drop all associated datafiles be they automatically or manually managed. Dynamic SGA The SGA can now be resized without having to restart the database. By issuing alter system commands you can resize the shared pool, large pool, buffer cache and log buffer. The buffer cache can only be dynamically resized if you are using the new DB_CACHE_SIZE parameter. You can also place a limit on the size of the SGA by using the SGA_MAX_SIZE initialisation parameter. Index Organised Tables Can now create and rebuild secondary indexes online. More Archiving Destinations You can now have 5-10 archive log destinations specified in the parameter file. Multiple Block Size Tablespaces can be created with non-standard block sizes (i.e. block sizes other than that specified by the DB_BLOCK_SIZE initialisation parameter). To use this feature you must specify a sub-cache for that block size by using the appropriate DBA_(n)K_CACHE_SIZE initialisation parameter. On-line Table Redefinition

2 Administration Resumable Space Allocation This excellent new feature allows you to resume large transactions that have failed due to some space allocation issue such as an object reaching its max extents or a user quota limit exceeded. Suspended transactions are noted in the alert log but a new trigger type (an after suspend trigger) can be used in conjunction with a new PL/SQL package to automatically deal with correctable errors. The Metadata API A new PL/SQL package, DBMS_METADATA, allows you to view metadata about a schema object in the form of DDL statements. Automatic Segment Space Allocation The locally managed tablespace feature which was introduced in Oracle 8i has now been enhanced so that the system can automatically manage space within segments as well as space within the tablespace. This means that Oracle uses bitmaps to manage space within segments instead of using freelists, the traditional method. This means that you no longer need to tune the PCTUSED, FREELIST and FREELIST GROUPS segment attributes. Cached Execution Plans Oracle 9i stores execution plans for cached cursors in a set of new dynamic performance views. This means you can find out a particular execution plan at a particular moment when, for example, performance issues have been noticed. Cursor Sharing By setting a dynamic parameter, you can tell the system to share SQL cursors for similar statements. This works by internally replacing literals in the statements with bind variables, thus automating what many application designers previously had to do manually. Database Resource Manager New functionality includes: the ability to create an active session pool for concurrent sessions; creation of an undo pool to allocate specific amounts of undo to certain user groups; prevent execution of operations that will last longer than a predefined limit and automatic switching of users between groups according to limits set by the administrator. Database Time Zone By specifying a time zone at database creation, the database can operate in a different time zone to the underlying operating system. Dates and times in transactions can also be resolved to the database time zone when applying data. Dynamic Job Queue Processes These processes are now spawned dynamically through a single co-ordinating process. This means that only the necessary numbers of job queue processes exist at any one time allowing more efficient memory usage. Fine Grained Auditing You can now audit in much greater detail than before. For example, you can use auditing to determine the nature of the data that someone has selected from a table as well as what operations they performed. This can be done either with triggers or with the help of a new PL/SQL package, DBMS_FGA. Monitoring Index Usage By using the alter index monitoring usage statement you can see if a particular index is being used. Usage data is then viewed through the v$object_usage system view. Multi-tier Materalised Views You can now build updateable materialized views on top of other updateable materialized views. This provides the ability to create complex branched replication environments, e.g. for

3 Administration Net8 and LDAP Net8 now supports an LDAP-Compliant directory service which acts as a central repository for database information, network components, user and corporate policies and preferences, user authentication and security information thus replacing local client-side and server-side files. This essentially replaces ONAMES but with the added benefit of being able to support heterogeneous systems and networks. The process by which Net8 resolves an alias into a connect descriptor using LDAP is called directory naming. Proxy Authentication Enables you to authorise a middle-tier server to act on behalf of a client. Server Parameter File (spfile) Initially created from a standard text parameter file, this new binary file is created and maintained on the machine housing the Oracle software. On-line parameter changes made using alter system commands are stored here meaning that such updates can persist across start-up and shutdown. Additionally you can start-up a database from a client by referencing the spfile in a parameter file on the client machine. Time-based Logfile Switching By setting a new ARCHIVE_LAG_TARGET initialisation parameter you can cause logfile switches at timed intervals provided there is redo information within the current archive log. Application Programming Java Object Persistance Has now been implemented: SQLJ object types can be associated with Java classes by using create type DDL. This allows both Java and SQL developers to be able to access these objects with ease meaning Java objects in the database can be stored and accessed in a standard way. Context Enhancements A new catalog index type (CTXCAT) means that Context search performance features can be used on data that exists in small chunks. New CTXRULE index type has been introduced for document classification applications. Enterprise Java Engine The renamed JServer from 8i comes with many new features, including the latest compliant engines for servlets and Java Server Pages; enhanced Corba and EJB support; better JDBC driver integration featuring type inheritance support and a native Java bytecode Accelerator and Memory profiler, for deployment performance. Oracle Text Oracle Text is the new name for InterMedia text as it is now a native feature. SQL and PL/SQL integration This has been tightened to improve performance. The overhead of calling PL/SQL procedures from SQL has been reduced. XML Datatype This new type stores XML content as a Character Large Object (CLOB). A number of built-in member functions enable developers to manipulate XML content. Additionally the XML type allows SQL operations on XML content and vice versa. XML SQL Functions Two new SQL functions have been added. SYS_XMLGEN allows dynamic production of XML documents from SQL select clauses. SYS_XMLAGG can aggregate multiple rowset returns

4 Application Programming ANSI Compliant Joins In an effort to improve portability by standards compliance, left and right outer join syntax is now available as well as syntax for full outer joins. Enhanced Unicode Support The NCHAR datatype has been reclassified in 9i to be used exclusively for Unicode character sets UTF8 and AL16UTF16. When specifying an NCHAR field length, you specify it in characters rather than bytes meaning you do not have to worry about space issues for multibyte character sets. Enhanced interoperability between NCHAR and other datatypes mean you can perform implicit and explicit conversions between the two as for other types. New Date-Time Datatypes Timezone-aware datatypes can automatically account for timezone differences in applications that are deployed globally. Using the time zone rules tables for a given region the time zone offset for a local time can be calculated, taking into consideration Daylight Savings time adjustments, and then used in further operations. Scrollable Cursors New cursor type in which you can move both forwards and backwards through the result set. Can use either absolute row numbers or relative row number offsets depending on your position in the result set. Additional memory usage enhancements have been included for greater efficiency. The LONG API This is a new API to help facilitate migrations from LONG to LOB datatypes. Helps ensure existing applications require as few changes as possible. XML PL/SQL Package The DBMS_XMLGEN package allows you to create XML documents from any SQL query by Backup and Recovery Features alter database end backup command Takes all datafiles out of backup mode in a single command. This new command allows you to script database crash recovery procedures without the need for user intervention. Flashback Queries By setting a new init.ora parameter (and having enough disk space!) you can cause the database to retain redo/undo information for a certain period of time. Then with the help of a new PL/SQL package, DBMS_FLASHBACK, you can retrieve old images of data in the specified timeframe and restore if necessary. Requires that you use the new automatic undo management feature. RMAN Enhancements Many new features have been introduced into the Recovery Manager, of which but a few are: Persistent configurations that can be created and applied to any session. This includes automatic channel configuration. Retention policy features that you can use to create a moving recovery windows for your database. Automatic control file backup and restore means that you can restore a control file even of the current control file and RMAN catalogue are lost. Block Media recovery to perform recovery of particular blocks in a datafile whilst that datafile is still online. Comes with a new dynamic view v$_database_block_corruption. Enhanced archive log backup features include the ability to switch log files before backing up the logs to produce a consistent state as you would in a self-scripted backup proce-

5 Backup and Recovery Features Fast Fault Recovery A new parameter, FAST_START_MTTR_TARGET, allows you to specify an expected mean time to recover. Oracle then automatically uses this value to set dirty buffer limits and limit the amount of redo generated since the last checkpoint by adjusting the rate at which information is written. Log Miner Enhancements The Log Miner from 8i has been significantly enhanced to include the ability to view DDL statements, direct path inserts and data dictionary information. In addition extra processing features include the ability to view collections of DML statements as transactions; place complex where clauses on the information you are extracting so you can see particular classes of statements and generate SQL redo and undo with primary key information to help the DBA rollback changes.all this is finished off with a brand new GUI, the Log Miner Viewer. Trial Recoveries You can now practice applying redo to the database in memory without ever writing the information to disk by using the SQL*Plus recover test command. This means that you can Business Intelligence Enhanced Query Rewrite Features Query rewrite can still be used (with materialized views) when the result set only contains some of the data (e.g. because the BETWEEN clause is being used). Change Data Capture New feature that allows incremental changes from target data sources to be captured and applied to the data warehouse automatically. Data Mining Incorporates Oracle data mining technology into the database so data, data preparation, model building, and model scoring activities all remain in the database and applications can be built on top. Includes important data mining algorithms. This is an optional extra. Improved Global Index Maintenance The new partition statement clause update global indexes causes Oracle to automatically maintain global indexes when table partitions are added/altered or dropped, giving improved efficiency and availability. Previously, global indexes had to be manually rebuilt when partitions were modified. Multi-Table Inserts Provides enormous performance benefits for large data loads by providing the ability to insert into more than one table with a single SQL statement. OLAP Server Scalable, high performance OLAP calculation engine. SQL merge Command Can dynamically decide whether to insert data or update current data during a load, depending on whether a corresponding row already exists in a table. Summary Advisor Wizard A new feature of the Enterprise Manager that provides an interactive environment in which to build and optimise materialized views. Helps you proactively optimise your aggregated data based on information gathered from workloads against the data or based on a hypothetical workload. Makes the most cost-effective trade-offs when recommending the creation of new materialized views and evaluating the performance of existing materialized views.

6 Business Intelligence Bitmap Join Indexes Provide for further performance improvements on join indexes (indexes that can span more than one table), especially in star schemas with fact and dimension tables. In addition, bitmap join indexes can eliminate some of the key iteration and bitmap merge work which is often present in star queries with bitmap indexes on the fact table. Data Block Pre-fetching This entirely transparent feature delays data block reads until multiple rows specified by the underlying index are ready to be accessed and then retrieves multiple data blocks at once, rather than reading a single data block at a time. This provides enormous performance gains for queries that are using indexes whose blocks are poorly clustered as it makes best use of system I/O capacity. External Table Define external files as tables in the data dictionary and be able to query them as you would ordinary Oracle tables. This provides for very fast data loads as you can load data from an external file using an insert into select from statement instead of using SQL*Loader. Also enables easy parallelism of data loads without having to split up the file to be loaded. List Partitioning A new partitioning method that allows you to specify discrete values on which to partition your table. Allows unordered and unrelated sets of data to be grouped and organised together according to data models. New Analytical SQL Functions 9i provides a number of new SQL functions to serve the Business Intelligence user including complex percentile calculations, ranks & distributions, new statistics and first/last aggregates. Range and Hash Partitioning Can now partition on all Oracle data types and table types such as IOT s. SQL with Clause Optimises query speed by eliminating redundant processing in complex queries. Enables a SELECT statement to define the subquery block at the start of the query, process the block just once, label the results, and then refer to the results multiple times. Table Functions Eliminate the need to stage data into physical objects during complex data transformation and load sequences. Using Oracle object types and object tables in PL/SQL, data can be dynamically passed through functions in sequence (known as pipelining ) and only the end result is inserted into a physical object. This additionally enables parallelism of the process because each stage of the process can run concurrently rather than one stage waiting for the