Database migration is the procedure and underlying methods of transferring databases from one database management system to the another. Companies often find the need to migrate their databases due to various reasons, including maintenance or upgrades, replacing server or storage equipment, migrating applications, consolidating websites, or relocating data centers. Database migration involves the transfer of all database objects and categories, including:
- Table Definitions: The structure and definitions of tables in the database are transferred to the target environment during the migration process.
- Data: The actual data stored in the tables is migrated to ensure that the target database contains the same information as the source database.
- Indexes and Constraints: Indexes and constraints defined on the tables are transferred to maintain data integrity and optimize query performance in the target database.
- Views: Views, which provide customized virtual representations of data, are migrated to ensure consistent functionality in the target environment.
- Triggers: Any triggers defined in the source database, which are automatically executed in response to specific events, are migrated to the target database.
- Stored Procedures and Functions: These database objects, containing sets of instructions to perform specific tasks, are transferred to maintain the desired functionality in the target environment.
- User Accounts, Roles, and Permissions: User accounts, along with their associated roles and permissions, are migrated to ensure proper access control and security in the target database.
During the database migration process, all these objects and categories are carefully transferred to the new database system, ensuring that the data and functionality are preserved accurately. By completing a successful migration, businesses and organizations can seamlessly transition their databases to a new environment while maintaining data consistency and operational continuity.
Database migration can be performed programmatically or manually using dedicated software called database migration tools. When transferring data manually, the process typically involves the following steps:
- Exporting table definitions, along with indexes and constraints, from the source database in the form of SQL statements.
- Converting these SQL statements into the destination format and importing them into the target database.
- Exporting the source data into CSV files using available open-source tools.
- Transforming the data according to the destination format and loading it into the target database.
- Exporting views, stored procedures/functions, and triggers into an SQL script.
- Converting these statements and code into the destination format and loading them into the target database. Although this step of the database migration may not be fully automated, there are tools available that can partially automate the process.
Once the data has been uploaded to the new system, it is important to verify the migration’s success and ensure that the new database supports the applications on the new platform. This verification process may require operating both the source and destination database systems concurrently to identify any discrepancies, prevent data loss, or address potential data corruption issues.
When undertaking a database migration project that involves a large and complex process, it is advisable to perform the migration programmatically. This approach automates the flow of the migration, saving human resources and alleviating the tedious tasks associated with the process. Choosing the right tool is essential to ensure a swift and seamless migration without data loss or corruption. High-quality database migration tools should provide the following necessary features:
- Support for all recent versions of both the source and destination database management systems (DBMS).
- Migration of schemas, indexes, and constraints with all related properties.
- Ability to store conversion settings into a profile for future use.
- Full Unicode support to handle diverse character sets.
- Option to customize types mapping and conversion rules according to specific requirements.
- Command line support for automated and scripted migrations.
- Comprehensive documentation and 24/7 support service to assist users during the migration process.
Numerous software companies offer tools and services to automate database migration. One such company is Intelligent Converters, specializing in database migration and synchronization since 2001. They have developed a range of conversion tools for migrating databases between popular DBMS platforms such as PostgreSQL, MySQL, Oracle, SQL Server, Azure SQL, Microsoft Access, FoxPro, and SQLite. For more detailed information about the company and their software, visit the official website of Intelligent Converters.