Compared to MySQL database, Oracle has the following advantages:

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1 To: John, Jerry Date: From: Joshua Li Subj: Migration of NEESit Databases from MySQL to Oracle I. Why do we need database migration? Compared to MySQL database, Oracle has the following advantages: 1. Oracle database is very stable, reliable and scalable. It is the best relational database. So far MySQL database has wasted our developers time on debugging and testing functions and features of the database engine itself. 2. Triggers and PL/SQL procedures can be used in Oracle to help application development and enhance performance 3. Oracle has better performance, backup and recovery. Oracle s hot backup allows backup in seconds while our current MySQL backup is done by daily batch. 4. Oracle database can handle very large amount of data up to TB scale. As database grows with project development and some of real data in files added to database, MySQL sever will reach a limit. Soon or later we have to migrate MySQL to a better database system. Now the database schema in MySQL is still simple and data amount small. The sooner we migrate database, the easier. 5. Oracle database is more secure. In addition, SDSC has very good license terms with Oracle Corporation, which also favors SDSC on NEES project. MySQL is not free as we currently pay $9000 a year for MySQL support. II. Why do we chose Oracle instead of other RDBMS? There are many different relational database management systems (RDBMS). These RDBMS vary significantly in their capabilities and in costs.

2 The popular vendors of RDBMS are listed below: RDBMS Vendors RDBMS Computer Associates INGRES IBM DB2 INFORMIX Software INFORMIX Oracle Corporation Oracle Microsoft Corporation MS Access Microsoft Corporation SQL Server MySQL AB MySQL NCR Teradata PostgreSQL Dvlp Grp PostgreSQL Sybase Sybase 11 Oracle, DB2 and SQL sever are the three leading RDBMS in the market. According to most recent statistic data from Gartner, Oracle, DB2 and SQL sever have 49%, 22% and 14~15%, respectively, for the worldwide RDBMS market for 2005 and The data of 2006 will be available in the coming May. Oracle and DB2 are usually used for large database on Unix platform while SQL Server for middle size on Windows platform. Please see attached two papers from eweek and Gartner on RDBMS market. Oracle is the best choice for NEESit considering the project scope, our infrastructure and other resource. Oracle Corp. gives very good license terms, nearly free, to SDSC. We have more people who used Oracle in NEESit group. We also can leverage Oracle expertise from Jerry, Joshua and others in SDSC. Oracle gives the highest quality and excellent support compared to other RDBMS vendors. Oracle on Linux platform has been used for several years. Once we migrate current NEES databases to Oracle, we can store some real data in file system to database by parsing them to tables or LOB types. DB2 has slight less functionality compared to Oracle although DB2 is also a very good enterprise

3 RDBMS. SQL sever does not fit to our Unix system. PostSQL and MySQL are usually slow, lacking database features, and not reliable and nor scalable for a large project. Other RDBMS are shrinking in database market and may be not available in the future. III. What are the Database Migration Tasks? The database migration involves changes in database system setup, schema modification, data migration, and application modification. It also needs good testing and a short period of down time of database sever and web site to finish the data migration and switch database sever and web application. Most development work will be in schema conversion and data migration in database side and modification of the persistent layer or mapper that connects database in application codes. It is suggested to let Kevin who charges the mapper or persistent tier of application to give more accurate estimation and details on the modification of application codes although some estimation on schedule is given below. I will focus on the work in database side. Task 1, to set up oracle database: This is basic database administration work: installation of Oracle RDBMS 10g, standard or enterprise version; creation of Oracle databases and instances for production, testing and development; user and role management, backup and recovery, and monitoring as well as tuning. Task 2, to modify schema of all database objects The SQL scripts of schema creation have a lot differences between MySQL and Oracle. First we need to fix incompatible objects in current database before we the migration. For example, some columns, named as comment, date, etc, cannot be used in Oracle. Then we can convert the MySQL script of the NEEScentral and NeesGA database schema to Oracle. We need not only to

4 modify the creation scripts of database objects but to add new database objects such as sequences for each table, multiple accounts for security control, etc. Finally we will run the script to set up schema for NEESit database in Oracle. The most conversion of schema from MySQL to Oracle, can be done by tools such as Sybase PowerDesigner, a tool from Quest Software, or Hibernate/EJB3 that was suggested by Kevin. This automatic conversion can save a lot of time though the generated codes usually need checking and modification manually. Additional Oracle database objects such as synonyms and sequences are still added mannuly. In addition, Hibernate/EJB3 also generates the database mapper or persistent tier for Java application, which also save time in Task 5 below of modification in application codes. It is suggested that Kevin or other Hibernate/EJB3 experts can make sure that upper PHP application can talk to Hibernate to connect to database. It is suggested that business rules should still be enforced by constraints and triggers in database although Hibernate can do in Java. Database tuning and other functions are still needed inside database. Task 3, to write scripts to migrate data There will be two scripts: to dump or export all data from MySQL database and to load the data to Oracle schema in Oracle database. Task 4, to support application developers on SQL and enhance database Some developers probably need help to use SQL on Oracle. The differences of SQL between Oracle and MySQL should be supported from database side. In addition, current database needs to add many database features available in Oracle database such as foreign keys, check constraints, indexes, triggers and PL/SQL procedures. Task 5, to modify application codes of PHP/Java to use Oracle database

5 All database related application codes in mapper or persistent tier which use SQL or database connection should be checked, and modified if needed, using Oracle database. Although most SQL for MySQL database should work well on Oracle database, data insertions need to add sequence if primary key column use sequence data. This part needs Kevin and other developers for details and schedule. Task 6, to test modified application on Oracle database After the modification of web application and database schema, a complete testing will be done to make sure new system works well in a development or testing environment. Task 7, To migrate production database and switch website A formal migration will be completed in a short period during which website is in either read-only mode or down. The migration will be performed using the tested scripts to load data from MySQL production sever to Oracle production server since both Oracle database schema and modified web application have been set up. Then production website will start to use Oracle production database after the migration. It is suggested a central testing and development Oracle database should be used. Data refreshment from production to testing and development databases will be performed by a DBA regularly. Appendix 1: ,00.asp eweek: Oracle Eats the Database Market Again

6 By Lisa Vaas May 24, comment posted Add your opinion Oracle ate the database market again in both Gartner and IDC numbers, here in PDF form, released May 24. According to Gartner's numbers for the worldwide RDBMS (relational database management systems) market for 2005, Oracle sat on the biggest slice 48.9 percent of the $13.8 billion pie, which grew 8.3 percent over 2004 numbers. ADVERTISEMENT IDC says the 2005 database market was $14.6 billion, up 9.4 percent over 2004 numbers. IDC granted Oracle a 44.6 percent share of that market, and said that Oracle's appetite grew 8.6 percent over what it took to fill the database king's belly in Oracle is, understandably, tickled pink to retain its hold on the market, in the two leading analyst firms' assessment. Willie Hardie, vice president of database product marketing for Oracle, said 2005 was a significant year given the release of Oracle Database 10g Release 2 in July. The polished release was what many customers were waiting for to get them to jump on the epic 10g database, he said. "That was a green light for our customers to increase their uptake of 10g," he said. "We saw significant increase of adoption in the second half of last year." RAC (Real Application Clusters) adoption continued to grow as well, Hardie said. Click here to read more about Gartner's assessment of Oracle's identity management. Meanwhile, penetration into the SMB (small to midsize business) market is going gangbusters, he said, what with Oracle's introduction

7 of the downsized Standard Edition 1. Another factor in Oracle's database dominion is Oracle Express Edition, Hardie said. That's given the company's inroads into the developer community, given the edition's drivers for PHP support and its better integration with.net, among other developer-friendly features. "We're seeing progress in three broad areas of the database community: the enterprise space, the SMB space, and the developer space," Hardie said. That's all well and good, said Gartner analyst Colleen Graham, principal research analyst on the market report. Not to pop Oracle's bubble or anything, but much of Oracle's success is actually coming at the expense of Oracle's own business, she said. To wit: Linux grew the fastest of all the RDBMS platforms, 84 percent, in Gartner's numbers. That growth was driven primarily by Oracle, as well as the maturation and acceptance of Linux as a mission-critical database platform. Appendix 2: ml Gartner Says Worldwide Relational Database Market Increased 8 Percent in 2005 With Increasing Popularity of Open Source and Evolving Buyer Models, Gartner Adjusts Methodology for Software Industry STAMFORD, Conn., 24 May Worldwide relational database management systems (RDBMS) total software revenue totaled $13.8 billion in 2005, an 8.3 percent increase from 2004 revenue, according to Gartner, Inc.

8 "The combined category of open source database management systems vendors, which includes MySQL and Ingres, showed the strongest growth, although it was one of the smallest revenue bases," said Colleen Graham, principal analyst at Gartner. "These open source DBMS products continue to improve in terms of functionality and scalability, and DBMS tool vendors are beginning to provide support for these offerings." The top 5 vendors accounted for nearly 92 percent of the total RDBMS market (see Table 1). Of the top 5 vendors, Microsoft was the only vendor to experience a growth rate above the industry average, mainly as a result of pent-up demand for SQL Server Gartner Dataquest's Software research group has traditionally measured market share in terms of new license revenue. However, due to the emergence and increasing popularity of open-source software and buyer consumption models such as hosted and subscription offerings, Gartner has moved to measure market share in terms of total software revenue which includes revenue generated from new license, updates, subscriptions and hosting, technical support and maintenance. Professional services and hardware revenue are not included in total software revenue. Table 1 Worldwide 2005 Vendor Revenue Estimates from RDBMS Software, Based on Total Software Revenue (Millions of Dollars) Compa ny Market Share (%) Market Share (%) Growth (%) Oracle 6, , IBM 3, , Microsof t 2, , Teradat a Sybase Other Vendors 1, , Total 13,817 12, Source: Gartner Dataquest (May 2006) Linux grew the fastest of all the RDBMS platforms (84 percent), driven primarily by Oracle, and the maturation and user acceptance of the Linux platform as a mission-critical DBMS platform. RDBMS on the mainframe platform continued to show strength, growing faster than the Unix platform, and even beating the overall growth rate.

9 Gartner analysts said the worldwide RDBMS market is poised for continued growth through 2010 as data management and integration take on a strategic importance in an increasing number of organizations "The market will see healthy growth, reflecting ongoing demand for relational database management systems used for online transaction procession, which has been the main driver of growth in the past," Ms. Graham said. "The market will also experience increased demand from organizations buying relational database management systems for business intelligence and data warehousing activities. The latter factor is being driven by an explosion of data that is being captured by organizations today." Gartner defines RDBMS as a database management system that incorporates the relational data model, normally including a Structured Query Language (SQL) application programming interface. It is a DBMS in which the database is organized and accessed according to the relationships between data items. In a relational database, relationships between data items are expressed by means of tables. Interdependencies among these tables are expressed by data values rather than by pointers. This allows a high degree of data independence. Additional information is available in the Gartner report "Market Share: Relational Database Management Systems by Operating System, Worldwide, 2005." The report provides market share results for the RDBMS market in Windows, Unix and Linux platforms. The report is available on Gartner?s Web site at CONTACT: Christy Pettey Gartner [email protected] About Gartner: Gartner, Inc. (NYSE: IT) delivers the technology-related insight necessary for its clients to make the right decisions, every day. Gartner serves 10,000 organizations, including chief information officers and other senior IT executives in corporations and government agencies, as well as technology companies and the investment community. The Company consists of Gartner Research, Gartner Executive Programs, Gartner Consulting and Gartner Events. Founded in 1979, Gartner is headquartered in Stamford, Connecticut, U.S.A., and has 3,700 associates, including 1,200 research analysts and consultants in 75 countries worldwide. For more information, visit