Methods of Oracle to MySQL Database Migration

For many years, Oracle has been renowned for its robust database management system that can handle large-scale corporate data warehousing. However, due to the high cost of its licenses, many organizations have sought out more affordable or free alternatives. Moving from Oracle to MySQL can bring several advantages, such as lower ownership costs, access to an open-source database engine, and a large community of MySQL professionals. Nevertheless, before deciding on which platform to use, it is crucial to consider the complexity and scale of the database being constructed.

Why Migrate from Oracle to MySQL

One of the most significant advantages of MySQL over Oracle is definitely the cost of licenses. Oracle is the most expensive database management system on the market, while MySQL is an open-source engine with a wide range of licenses available for free. This implies that businesses can save a significant amount of money by switching to MySQL. Additionally, MySQL and its forks, such as MariaDB and Percona, Besides, MySQL is integrated well with the web making this DBMS an appealing choice for web developers.

Another crucial advantage of migrating to MySQL is the large community of database professionals. Due to the open-source nature of MySQL, many professionals with deep expertise in the technology can provide support when required. This is not the case with Oracle, which can be more challenging and expensive to find experienced professionals in database administration or development fields.

However, if someone is building a complex corporate-scale database, Oracle may still be the better choice due to its ultimate functionality and flexibility.

Manual Migration

The process of migrating from Oracle to MySQL, MariaDB, or Percona involves several steps. First, all table structures are exported into data definition language (DDL) statements, which are then made compatible with MySQL format and imported into the target database. Next, all data is exported into an intermediate CSV warehouse, which is updated to comply with MySQL syntax and loaded into the database. Oracle primary keys, indexes, and relationships between tables are extracted as CREATE-statements, migrated into MySQL format, and imported into the target database.

Furthermore, since MySQL does not support sequences, Oracle sequences must be emulated by the AUTO_INCREMENT property of the corresponding column when appropriate, or by using temporary tables for more complex requirements. Oracle views, triggers, stored procedures, and functions are extracted as SQL statements and source code, then rewritten according to MySQL dialects of SQL and loaded into the target database. This step requires deep programming knowledge in both Oracle and MySQL dialects of SQL.

Use Commercial Migration Tools

While it is possible to migrate from Oracle to MySQL manually, this approach can be time-consuming and error-prone. To prevent issues such as data loss or corruption, it is recommended to use specialized software tools that automate the Oracle to MySQL database migration process. One such solution is the Oracle to MySQL converter provided by Intelligent Converters, a company with over 20 years of experience in database migration and synchronization.

Key features of the Oracle to MySQL converter include support for all modern versions of Oracle and MySQL, including forks (MariaDB, Percona) and cloud variations (Amazon RDS, Azure for MySQL, Google Cloud, etc.), migration of schemas, data, primary keys, indexes, and relations between tables with respect to differences between Oracle and MySQL, pre-processing of data to migrate (filtering, merging multiple tables into one, etc.) via SELECT-queries, and command-line support for scheduling and scripting Oracle to MySQL database migration.

Oracle to MySQL Migration Steps

When using Oracle to MySQL converter, it will guide you through all migration steps using intuitive wizard-style GUI.

First, user has to specify whether he want to migrate Oracle database to MySQL directly or export it into script file containing SQL statements to create all database objects and fill tables with the data.

Then it is required to specify Oracle connection details such as server, database name, user and password.

If you select ‘Move to MySQL server directly’ option, on the next you have to enter all details to connect to MySQL server such as MySQL server (if it is not a localhost), username, password and port (if it differs from default 3306).

If you selected ‘Store into dump file’ option on the first step, now it is time to specify MySQL dump file settings: version of MySQL syntax, line breaks and other formatting options.

On the next step user has to specify migration settings such as strings sensitivity in the target database, to not convert indexes, data, etc.

Next step is to select Oracle tables for migration to MySQL. You can customize appearance of every table in the destination MySQL database (modify name, type and other attributes of every column as well as exclude some of them from migration) by double-click on the corresponding item in ‘Selected tables’ list.

If Oracle database contains views, you need to select which of them are migrated on the next step of the wizard.

After completing all of the steps listed above, database migration will be launched.

To summarize, transitioning from Oracle to MySQL can bring several benefits, such as reduced ownership costs and access to an open-source database engine. However, it is crucial to carefully consider the complexity and size of the database being created, as Oracle may still be the superior choice for large corporations that require advanced tools and functionality. Additionally, utilizing specialized software tools to streamline the migration process is recommended to prevent data loss or corruption.