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Oracle® Migration Workbench User's Guide
Release 10.1.0 for Microsoft Windows 98/2000/NT/XP and Linux x86
Part No. B15857-01
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2 Preparing a Migration Plan

This chapter describes the process of how to create a migration project plan. It identifies the sections you must include in the migration plan, describes how to determine what you must include for each section, and how to avoid the risks involved in a migration project. This chapter includes:

Task 1: Determining the Requirements of the Migration Project

In this task, you identify which databases you want to migrate and applications that access that database. You also evaluate the business requirements and define testing criteria.

To determine the requirements of the migration project:

  1. Define the scope of the project.

    There are several choices you must make about the third-party database and applications that access that database in order to define the scope of the migration project. To obtain a list of migration issues and dependencies, you should consider the following

    • What third-party databases are you migrating?

      • What is the version of the third-party database?

      • What is the character set of the third-party database?

    • What source applications are affected by migrating the third-party database to an Oracle database?

      • What is the third-party application language?

      • What version of the application language are you using?

      In the scope of the project, you should have identified the applications you must migrate. Ensure that you have included all the necessary applications that are affected by migrating the database

    • What types of connectivity issues are involved in migrating to an Oracle database?

      • Do you use connectivity software to connect the applications to the third-party database? Do you need to modify the connectivity software to connect the applications to the Oracle database?

      • What version of the connectivity software do you use? Can you use this same version to connect to the Oracle database?

    • Are you planning to rewrite the applications or modify the applications to work with an Oracle database?

  2. Use Table 2-1 to determine whether you have a complex or simple source database environment. Identify the requirements based on the specific scenario.

    If the migration project is a simple scenario, you may not have to complete all of the tasks listed in this guide. You make decisions based on your specific environment. For example, if you have a complex scenario, you may require extra testing based on the complexity of the application accessing the database.

    Table 2-1 Complex and Simple Scenarios

    Complex Scenario Simple Scenario
    More than one of the following:
    • Large database (greater than 25 GB)

    • Data warehouse

    • Large applications (greater than 100 forms, reports, and batch jobs)

    • Database is used by multiple lines of business

    • Distributed deployment

    • Large user base (greater than 100)

    • High availability requirement (such as a 24 X 7 X 365 environment)

    Contains the following:
    • Small database (less than 25 GB)

    • Simple online transaction processing (OLTP)

    • Small application (less than 100 forms, reports, and batch jobs)

    • Database is used by one department

    • Centralized deployment

    • Small user base (less than 100)

    • Average availability (business hours)


  3. Determine whether the destination database requires additional hardware and rewriting of backup schedules.

  4. Define testing and acceptance criteria.

    Define tests to measure the accuracy of the migration. You then use the acceptance criteria to determine whether the migration was successful. The tests that you develop from the requirements should also measure stability, evaluate performance, and test the applications. You must decide how much testing is necessary before you can deploy the Oracle database and applications into a production environment.

  5. Create a requirements document with a list of requirements for the migration project.

    The requirements document should have clearly defined tasks and number each specific requirement, breaking these into sub-requirements where necessary.

Task 2: Estimating Workload Using Migration Workbench

In this task, you use Migration Workbench to make calculated decisions on the amount of work that can be automated and how much is manual.

To use Migration Workbench to estimate the workload:

  1. Use Migration Workbench to capture the Source Model, create the Oracle Model, and migrate to the destination database.

    Migration Workbench allows you to analyze the source database through the Source Model and a preview of the destination database through the Oracle Model. After you have captured the source database, analyze the captured data contained in the Source Model and the Oracle Model. Ensure the content and structure of the Workbench repository is correct and determine how much time the entire process takes.

  2. Generate and use Migration Workbench reports to evaluate the capture and migration process, categorize the total number of database objects, and identify the number of objects that can be converted and migrated automatically.

    The Summary, Detailed, and Error and Warnings reports provide information about the actions that have occurred and record any warnings and errors. They identify the changes that have been made to the Oracle Model so that you can evaluate if you should make changes to the applications that access the destination database.

  3. Evaluate and categorize the issues that occurred while running Migration Workbench. Migration Workbench reports can help by providing information about:

    • Tables that did not load when you captured the source database

    • Stored procedures, views, and triggers that did not parse when you created the Oracle Model

    • Syntax that requires manual intervention

    • Database objects that were not created successfully when you migrated the destination database

    • Data that did not migrate successfully when you migrated the destination database

  4. For each error or warning in Migration Workbench reports, evaluate the following:

    • Number of times an issue occurred

    • Time required to fix the issues, in man hours

    • Number of resources required to fix the issue

      After you have solved a complex problem, it should be easier and quicker to resolve the next time you have the same problem.

    Use these reports to evaluate each error and determine how long it would take to rectify. The reports help identify the size of the database that Migration Workbench has created.

Task 3: Analyzing Operational Requirements

In this task, you analyze the operational requirements, as follows:

  1. Evaluate the operational considerations in migrating the source database to a destination database. Consider the following questions:


    Note:

    If the scope of the migration project is a complex scenario as defined in Table 2-1, Oracle recommends that you answer all of these questions. If you have a simple scenario, determine the answers to the most appropriate questions.

    • What backup and recovery changes do you require?

    • What downtime is required during the migration?

    • Have you met the performance requirements?

    • Are you changing the operational time window?

    • What effect does the downtime have on the business?

    • What training requirements or additional staff considerations are required?

    • Is it necessary to have the third-party and the Oracle database running simultaneously?

  2. For each task, determine the resources and time required to complete.

  3. Create an initial project plan.

    Use the information that you have gathered during the requirements and planning stage to develop an initial project plan.

Task 4: Analyzing the Application

In this task, you identify the users of the applications that run on the source database, what hardware it requires, what the application does, and how it interfaces with the source database. You also analyze the method the application uses to connect to the database and identify necessary modifications.


Note:

If the migration project is a complex scenario as defined in Table 2-1, Oracle recommends that you answer all of these questions. If you have a simple scenario, determine the answers to the most appropriate questions.

To analyze the application:

  1. Determine whether changes to the application are required to make them run effectively on the destination database.

  2. If changes are required to the application, determine whether it is more efficient to rewrite or modify the applications.

    If you are rewriting the application to use the Oracle database, consider the following:

    1. Create the necessary project documentation to rewrite the application. For example, you need a design specification and requirements documentation.

    2. Rewrite the application according to the specification.

    3. Test the application works against the Oracle database.

    If you are modifying the application to use the Oracle database, consider the following:

    1. Identify the number of connections to the database that are in the application and modify these connections to use the Oracle database.

      You may need to change the connection information to use an ODBC or JDBC connection.

    2. Identify the embedded SQL statements that you need to change in the application before you can test it against the Oracle database.

    3. Test the application using the Oracle database.

  3. Allocate time and resource to address each issue associated with rewriting or modifying the application.

  4. Update the general requirements document for the project that you created in Task 1.

Task 5: Planning the Migration Project

In this task, you evaluate the unknown variables that the migration project may contain, such as the difference in the technologies of the source database and the destination database. During the planning stage, you:

To plan a migration project:

  1. Define a list of tasks required to successfully complete the migration project requirements of Task One.

  2. Categorize the list of tasks required to complete the migration project.

    You should group these tasks according to your business. This allows you to schedule and assign resources more accurately.

  3. Update and finalize the migration project plan based on the information that you have obtained from Task 3 and Task 4.

  4. Make sure the migration project plan meets the requirements of the migration project.

    The migration plan should include a project description, resources allocated, training requirements, migration deliverable, general requirements, environment analysis, risk analysis, application evaluation, and project schedule.