Assessing your on-premises database for migration
As part of your migration project, you must perform a comprehensive review, not only of your Pega applications, but also the systems that support them. Performing a database gap analysis is a milestone activity during which you identify any potential modernizations required in order to migrate your deployment to a Pega Cloud environment, including a plan to implement these changes.
Preparing to migrate your database
Before migrating, you must thoroughly review your on-premises database setup, to assess where you will need to make upgrades and changes. Gather comprehensive details about your Pega database structure – your database type and version, size of tables, schemas used, your backup strategy and retention policy, and other information.
In addition, there may be legacy functionality which is not supported in Pega Cloud Services environments. (See Pega Cloud Services and Legacy Functionality in the Migration Overview article.) These out-of-date structures must be identified and replaced with secure, guardrail-compliant functionality for migration to Pega Cloud Services.
IMPORTANT: Pega Cloud uses the Amazon Relational Database Service (RDS) for PostgreSQL. All your database functionality must be compatible with the PostgreSQL database.
Gathering database information
To assist in this assessment, Pega provides the Client Cloud Migration Gap Assessment Worksheet, which lists all the information to be gathered, and highlights out-of-date functionality. For your database structures, please complete the Database Analysis sheet.
After you have completed your purging or archiving (see Reviewing your database information in the next section), you need to record information about your database. As shown in the Worksheet, information to gather before a migration includes:
- Database vendor type and version
- Size of the tables in the rules schema
- Size of the tables in the data schema
- Memory, CPU, and data storage allocated for production database
NOTE: You would not want to gather this information before purging/archiving, as the table sizes will change during the purging/archiving process.
If you have been using Pega software for a number of years, there may be data that you don’t have to move. Moving old data can be a complex process. All applications evolve, and your data may contain information for old properties or data fields for parts of your application which are no longer being used. It may be easier to purge or archive some old data tables rather than attempt to map these old properties to your newer functionality.
Reduce the overall size of the database
Instead of attempting to move a huge database that has been growing for years, consider whether you could purge or archive records. If you will never need those records again, purging is a viable option.
Many companies are in an industry which requires that all records be kept for a specified period of time (example: 7 years). If purging is not an option for your records, you might want to archive them. Either of these choices can reduce the number of data records that you need to migrate.
For full details, see Saving space on your system by purging and archiving old work items.
Determine whether database tables require full or partial migration
There may be tables with old properties, or tables which are entirely out-of-date. Review your database tables, and see which tables require:
- Remediation or cleanup
- Partial migration
- Full migration