Version 5
DB2 Connect provides a managed method to access databases stored on the following systems:
DB2 Connect provides access to those databases in a cost-effective way by
implementing a standard architecture for managing distributed data, known as
Distributed Relational Database Architecture (DRDA). Use of DRDA allows
applications to establish a fast connection to host and AS/400 databases
without expensive host components or proprietary gateways.
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Version 5
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TCP/IP has been added as a second protocol (the other being SNA) over which DB2 Connect can communicate to host systems. Also, DB2 servers are enabled to accept incoming DRDA connections from the host using TCP/IP. In other words, DRDA Application Requester (AR) and DRDA Application Server (AS) functionality has been implemented using TCP/IP in addition to SNA. See the DB2 Connect Enterprise Edition Quick Beginnings and the DB2 Connect User's Guide for details.
DRDA two-phase commit for the DB2 DRDA Application Requester (DB2 Connect) over the TCP/IP communications protocol has been implemented.
In addition, applications running on the host (for example, DB2 for MVS/ESA applications) using SNA can invoke the two-phase commit processing involving both the host and DB2 Version 5 databases. See the DB2 Connect Enterprise Edition Quick Beginnings and the DB2 Connect User's Guide for details.
See "Two-Phase Commit Enhancements for Version 5.2" for additional enhancements to two-phase commit in Version 5.2.
The ability to execute stored procedures on DB2 for OS/390 is greatly improved. Applications can now receive multiple open cursors from stored procedures executing on DB2 for OS/390. Each cursor can have multiple rows. See the DB2 Connect Enterprise Edition Quick Beginnings and the DB2 Connect User's Guide for details.
Support is added for the Open Software Foundation's (OSF) Distributed Computing Environment (DCE) Security component for use in authentication of database users. This provides both a more secure authentication mechanism and more central management of users, passwords, and groups using the DCE architecture.
In addition, DCE Cell Directory support is available for DB2 for OS/2. The supported protocols are APPC, TCP/IP, NetBIOS, and IPX/SPX.
The restriction on AIX and other UNIX platforms that the SYSADM_GROUP must
be the primary group of the instance owner is removed. See the Administration Guide for details.
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Version 5.2
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Users working with host and AS/400 databases servers now have additional options for providing database location information when using DCE Cell Directory support for implementations from IBM and Gradient. See the Administration Guide for details.
Users connecting to host and AS/400 databases can now get additional information on the cause of security failures when they occur, for example as the result of an expired password. See the DB2 Connect Quick Beginnings manuals for details.
DB2 Connect Enterprise Edition (EE), and the DB2 Connect component that is included in both DB2 UDB EE and DB2 UDB Extended - Enterprise Edition (EEE), can now provide enhanced load balancing and fault tolerance by routing connections to different nodes on a System/390 SYSPLEX. Some additional configuration considerations apply, and these are documented in the DB2 Connect Enterprise Edition Quick Beginnings manual.
A new tool db2ocat - DB2 ODBC Catalog Optimizer is provided on Windows 32-bit operating systems in order to help you optimize system catalog searches for ODBC applications. DB2 Connect now offers a way to dramatically improve the performance of ODBC and JDBC applications that make extensive use of the system catalog. This improvement is provided using the CLISCHEMA parameter in the db2cli.ini file, which allows applications to use an ODBC-optimized catalog instead of the regular system catalog tables. A point-and-click application that simplifies the creation and maintenance of ODBC-optimized catalogs can be obtained by downloading db2ocat.zip from ftp://ftp.software.ibm.com/ps/products/db2/tools.
There are two new enumerated values for the DYNAMICRULES parameter of the BIND command. DEFINE and INVOKE are used to specify the authorization identity to be used for the execution of a dynamic SQL statement in a user-defined function (UDF) or stored procedure. See the Command Reference for details.
DB2 family databases (including host and AS/400 databases) can now fully participate in distributed transactions managed by the Microsoft Transaction Server (MTS). See "Microsoft Transaction Server" and the DB2 Connect Enterprise Edition Quick Beginnings manual for details.
DB2 Universal Database and DB2 Connect now provide the ability to manage passwords without requiring users to log on to database server machines. Passwords can be changed using the SQL CONNECT statement, by requesting a password change from the ODBC login dialog, or by using the ATTACH command. The ability to change user passwords is provided for Embedded SQL, ODBC, DB2 CLI, and Java (using JDBC and SQLJ).
For OS/390 users, if an SQL CONNECT statement returns a message indicating that the user ID's password has expired, it is now possible to change the password without signing on to TSO. Through DRDA, DB2 for OS/390 can change the password for you. An additional benefit is that with TCP/IP connections to the host, a separate LU definition is no longer required, as was the case with DB2 Connect Version 5.0. See the DB2 Connect Enterprise Edition Quick Beginnings manual for details.
The new sqleseti - Set Client Information API allows three-tier client/server or TP monitor applications to pass more specific information about the application end user to DB2 for OS/390 (see "Client Information"). The new information includes the end user name supplied by the server application, the workstation name, the application name, and the accounting string. This information can now be reported by the DB2 for OS/390 DISPLAY THREAD command and it is available in DB2 for OS/390 accounting records. Previously, in three-tier environments, DB2 for OS/390 could only provide information about the server application and the individual authentication user ID, and not about the numerous end users who multiplex SQL queries on long-running connections. See the API Reference and "Transaction Processor Monitoring" for details.
DB2 Connect now provides complete support for working with host and AS/400 databases configured for bidirectional languages such as Arabic and Hebrew. See "Bidirectional CCSID Support" and the Administration Guide for details.
The capabilities of the database system monitor have been expanded to collect more information on DB2 Connect applications. These enhancements include the ability to collect information on DCS applications running at the gateway, SQL statements being executed, and database connections. See "System Monitoring for DB2 Connect" for more information.
In DB2 Connect Enterprise Edition Version 5.0, two-phase commit support over SNA connections using the DB2 Syncpoint Manager (SPM) was only available on AIX and OS/2 (see "Two-Phase Commit"). With DB2 Connect Enterprise Edition Version 5.2, this support is now extended to Windows NT. This support requires IBM eNetwork Communications Server for Windows NT Version 5.01 or higher (see "DB2 Connect for Personal Communications").
Two-phase commit for XA applications was previously only supported over SNA connections, using the SPM. It is now also supported over TCP/IP connections using the SPM.
Applications executed by Transaction Processing Monitors such as IBM TXSeries, CICS for Open Systems, Encina Monitor, and Microsoft Transaction Server previously had to access host systems such as DB2 for OS/390 using SNA. With DB2 Connect Version 5.2, TCP/IP can now be used by these same applications. The DB2 Syncpoint Manager must be used to enable this new feature.
See the DB2 Connect Quick Beginnings manuals for details.
DB2 Syncpoint Manager configuration has been simplified. Many steps are now automated or eliminated compared to previous releases. See the DB2 Connect Quick Beginnings manuals for details.
DB2 Connect Version 5.2 now provides support for big integer (BIGINT), large object (LOBs), and user-defined distinct data types (UDT). See the SQL Reference for details.
DB2 Connect for Personal Communications is a component of IBM eNetwork Personal Communications for Windows 95 and Windows NT. It provides many of the functions available with the DB2 Connect Personal Edition with the following limitations:
IBM eNetwork Personal Communication customers that need these additional functions should upgrade to DB2 Connect Personal Edition or DB2 Connect Enterprise Edition products.