Client Connectivity for Oracle Rdb

Client Connectivity for Oracle Rdb Colleen Mitchneck Linda Kipnes Bryan Alvey 2004-2005, Oracle Corporation

Client Connectivity When we talk Client Connectivity to Rdb, we are talking about Oracle SQL/Services for Rdb 2

History of SQL/Services 1992: Initial Release Implemented a SQL/Services client API Implemented an ODBC for Oracle Rdb driver allowing any industry standard ODBC application to use Rdb in the backend 1994: SQL/Services acquired by Oracle 1995: Added RMU client/server capabilities 3

History of SQL/Services 1996: Implemented Oracle Call Interface (OCI) support OCI applications could now run almost transparently against an Rdb database As new industry standards emerge, Oracle implements compliant OCI drivers (JDBC,.NET, etc.), which function with Oracle and Rdb databases in the backend 2003: Added Oracle Rdb JDBC server management 4

SQL/Services Architecture Client Server Desktop systems Monitor Configuration File Dispatcher Client applications SQLSRV_MANAGE SQLSRV Service RMU Service OCI Service Executors SQL/Services Manager GUI Rdb databases 5

SQL/Services Protocols SQLSRV used by applications based on ODBC or on the SQL/Services client API OCI used by Oracle applications that communicate via the Oracle Call Interface (OCI) protocol RMU used by the Oracle Rdb RMU utility for parallel backup and remote command execution JDBC used to start and stop JDBC for Oracle Rdb thin servers 6

SQLSRV Client Architecture Client using SQL/Services client API directly Client Application SQL/Services Client API Client using ODBC for Oracle Rdb Client Application ODBC for Oracle Rdb SQL/Services Client API server 7

SQLSRV Client SQL/Services client API Available on Windows, Tru64 UNIX, OpenVMS, Red Hat Linux Red Hat Linux (V2.1 or later) is a new platform for Oracle SQL/Services release 7.1.6 Includes a library of routines that client applications can call to access SQL/Services functions Enables client applications to execute Oracle Rdb dynamic SQL statements against an Rdb database 8

SQLSRV Client ODBC for Oracle Rdb Layered on the client API to provide industry standard ODBC access to Rdb Current version 3.1.0.2 Much improved over earlier versions Better performance Improved conformance with ODBC specification New API calls and prefetch functionality 9

SQLSRV Client ODBC for Oracle Rdb (con t) Works with any ODBC compliant application ADO,.NET via bridge many different vendors have released ODBC-compliant applications in the software development, office productivity, and data analysis space Portable across databases 10

SQLSRV Server Architecture SQLSRV_MON monitor SQLSRV_DISP dispatcher Client SQLSRV_EXEC executor Rdb databases 11

SQLSRV Server Monitor (SQLSRV_MON) provides overall management and control for the server Dispatcher (SQLSRV_DISP) responsible for handling network communications for the clients and for the routing and scheduling of client requests to executors of a service a single dispatcher typically supports more than one network protocol, but can support a single protocol Executor (SQLSRV_EXEC) accepts client requests from dispatchers, processes them, and returns the results there is a pool of executor processes for each service 12

OCI Client Architecture Client OCI Client Application Oracle Net Server 13

OCI Server Architecture SQLSRV_MON OCI_DISP dispatcher Client SQLSRV_SQLNETSHR (Oracle RDBMS libraries) SQLSRV_NATCONN RDB$NATCONN (OCI Services) Rdb databases 14

OCI Protocol Presents an Oracle RDBMS view of an Rdb database by emulating Oracle Data Dictionary Manages Oracle cursors Manages Oracle to Rdb data type conversions Provides functions to emulate Oracle RDBMS built-in functions (to_date, etc.) 15

OCI Protocol Some of the products using OCI Oracle JDBC Oracle ODBC Oracle database links Oracle Data Provider for.net Oracle Reports 16

OCI Protocol And more products using OCI Oracle JDeveloper Oracle Forms Oracle Designer Oracle Developer Oracle SQLPLUS utility And many, many others 17

18 OCI Protocol Connecting from Java

RMU Protocol Architecture client SQLSRV_MON server RMU_DISP dispatcher Client RMU Command Line Utility RMUEXEC RMUSHR Rdb databases 19

RMU Protocol RMU/BACKUP/PARALLEL BACKUP command is sent from RMU client through SQL/Services to the server node, where the backup is done by RMU executors Each RMU executor process can run multiple backup threads. Remote RMU Command Execution Executes RMU commands remotely based on user specified logical definitions 20

21 SQL/Services Management SQLSRV Command Line

22 SQL/Services Management GUI based Manager

23 SQL/Services Management Enterprise Manager 9i

SQL/Services 7.1.6 Currently in beta test Production release planned for Q1 2005 Major Features Upgraded to use the Oracle 9.2.0.4 libraries 2pc Support New and updated utilities Performance enhancements 24

SQL/Services 7.1.6 Upgrade to Oracle 9.2.0.4 Upgraded OCI Services Added support for new Oracle 9i data types Time, Year-to-month interval, Day-to-second interval, etc. Removed several restrictions when connecting from Oracle 9i 25

SQL/Services 7.1.6 2pc Support Oracle Rdb databases can now fully participate in Oracle RDBMS managed distributed transactions Allows multiple Oracle server DBLINKs to Rdb databases to participate in a transaction Exploits DECdtm XA Gateway to provide interface between Oracle distributed transaction protocol and DECdtm distributed transaction protocol 26

What is a DBLINK? A DBLINK is a Oracle RDBMS database serverto-server connection Set up in the Oracle RDBMS database with SQLPLUS: SQL> CREATE DATABASE LINK dblink_name 2 CONNECT TO "username" IDENTIFIED BY 3 "password" USING "service_name"; Uses a server-to-server subset of the OCI protocol OCI Native Connection (NATCON) NATCON is a remote call interface Implementation in Rdb uses SQL Services SQL Services Dispatcher resolves connection SQL Services Executor implements OCI Interface SQS Executor translates Oracle SQL into Rdb SQL 27

Transactions on a DBLINK OCI NATCON Transaction interface Not SQL sentences like SET TRANSACTION RCI calls to transaction functions in OCI Services I/F: gtabegn(), gtaprtn(), gtacomm(), gtaroll(), gtafrgt(), gtareco() Implemented inside the SQL Executor Uses Oracle RDBMS internal transaction protocol Distributed transaction capable 2 Phase Commit (i.e. prepare and commit/rollback) Allows partner to decline 2PC XA-like protocol but not XA 28

What s the Problem with DBLINK 2PC and Rdb? Rdb supports distributed transactions but It uses DECdtm as the transaction manager It requires DECdtm AST calls to manage transaction SQS Executor would need a DECdtm TID Would pass TID to Dispatch layer in context structure Dispatch layer would join the DECdtm transaction Rdb recovery asks DECdtm for transaction status Oracle RDBMS Server doesn t do DECdtm SQS Executor has to decline 2PC Oracle RDBMS server copes by calling DBLINK to commit after other participants successfully prepare Limits transaction to one Rdb DBLINK participant 29

HP to the Rescue DECdtm XA Gateway provided by HP Interfaces an XA Transaction Manager (TM) to DECdtm Allows DECdtm Resource Manager (RM) like Rdb to participate in an XA transaction Released as part of OpenVMS 7.3-1 Can be exploited for DBLINK 2PC Oracle RDBMS protocol is similar and compatible Interface written for OCI to XA Gateway SQS Executor translates between protocols Can now participate in distributed transactions One DBLINK limit removed 30

Gory Details of Implementation SQS Executor is a SQL$PRE/CC application Now compiled specifying implicit 2PC Executor s Rdb Dispatch layer joins the default DECdtm transaction SQS Executor now sends OCI transaction calls to XA Gateway OCI transaction ID is used as an XA transaction ID XA Gateway calls DECdtm Sets SQS Executor process default transaction Passes transaction calls for that transaction DECdtm calls Dispatch layer of SQS Executor via ASTs SQL statements submitted dynamically as before 31

Gory Details Illustrated Oracle RDBMS Server OCI NATCON SQS/OCI Executor Dynamic SQL XA Calls XA Gateway Server DECdtm Calls Rdb Dispatch SQS Executor Process DECdtm Calls DECdtm Services 32

How Do I Use It? Set up the DECdtm XA Gateway Make sure Gateway server is installed: DDTM$XG_SS.EXE Use Gateway Control Program (XGCP.EXE) to: Create a log for your XA domain Start up the Gateway server Define Rdb logical for XA Gateway domain Logical name: RDB$DDTM_XG_INFO For example: $DEFINE/SYSTEM RDB$DDTM_XG_INFO SYSTEM$node_name where node_name is the OpenVMS node name Now SQL Services will automatically do 2PC 33

SQL/Services 7.1.6 Utilities RDB$NATCONN_DIC Utility New utility for 7.1.6 Replaces the use of.sql scripts required by prior versions Performs database prepare, upgrade and drop of Oracle data dictionary definitions in Rdb database to enable OCI access Can upgrade from any prior version of OCI Services (no interim upgrades required) Invoked via SYS$LIBRARY:RDB_NATCONN.COM 34

SQL/Services 7.1.6 Utilities RDB$NATCONN_CUPP Utility Updated utility for 7.1.6 Replaces RDB_NATCONN procedure to add users Used to add, modify, remove, and show users enabled for OCI access Most OCI applications now require users to be defined in the database in order to execute the application Invoked via SYS$LIBRARY:RDB_NATCONN.COM 35

SQL/Services 7.1.6 Performance Enhancements SQLSRV_SQLNETSHR71.EXE Expanded to include both Oracle SQLNET and OCI libraries Installed shareable to decrease memory usage and increase performance Oracle OCI libraries no longer built into OCI Services images; each image ~9,000 blocks smaller than release 7.1.5.9.1 Results in a smaller footprint for each running OCI executor process 36

SQL/Services 7.1.6 Performance Enhancements More efficient metadata queries in OCI Services Queries are now prepared once on first use and executed numerous times, rather than being prepared each time query is executed More efficient use of shared memory in SQL/Services to eliminate memory leaks 37

SQL/Services 7.1.6 Other New Features Automatic creation of LISTENER.ORA file during installation, if it doesn t already exist Validate program feature to restrict users to access via user specified programs JDBC dispatcher; used to start and stop JDBC for Oracle Rdb thin servers OCI Services bugcheck dump capability Documentation update & reorganization Installation guide Configuration guide Release notes 38

SQL/Services Futures? Production Release 7.1.6 Q1 2005 Upgrade to Oracle 10G OCI transaction reuseable services ODBC on Linux? Enhanced BLOB support VMS external authorization support Support for new Oracle packages User defined packages 39

40 SQL/Services Future - EM10g Grid Control

Questions? Colleen.Mitchneck@oracle.com 41