By Hassan Shareef — Database Administrator, 16 years' experience
Converting from MSSQL to MySQL often becomes imperative for organizations seeking to migrate their database management systems — driven by cost-effectiveness, scalability, and compatibility requirements. For example, a company might run a website backend on MySQL while using Microsoft SQL Server for internal applications, requiring DBAs to frequently migrate data between the two.
Fortunately, there are numerous tools available to facilitate this conversion, each with its own strengths. This article offers insight into choosing the right tool for your organization's needs.

Microsoft SQL Server is a popular relational database management system (RDBMS) developed by Microsoft. It provides powerful tools for storing, managing, and retrieving data, and is widely used in enterprise-level applications, web applications, and other software systems.
It uses SQL to manage and manipulate data, with features like backup and restore, replication, clustering, reporting, analysis, and data mining, and integrates with Excel, SharePoint, and Visual Studio. It supports C++, C#, Java, PHP, and Python, runs on Windows, and is available in Express, Standard, Enterprise, and Developer editions.

MySQL is an open-source RDBMS originally developed by MySQL AB and now owned by Oracle Corporation. It's one of the most popular and widely used database systems in the world, powering many web applications and content management systems.
MySQL is a client-server system usable with C, C++, C#, Java, PHP, Python, and Ruby, offering replication, backup and recovery, clustering, and partitioning. It's available under the GNU General Public License (GPL) and can be downloaded and used for free, with commercial versions also available.
MySQL is open source and free, while MS SQL Server is a commercial product requiring a license that can be expensive.
MySQL runs on Windows, Linux, and macOS. MS SQL Server is primarily designed for Windows, with limited support elsewhere.
MySQL is known for fast performance and scalability. MS SQL Server performs well but may need more hardware for larger databases.
MySQL has a very large developer community contributing support, plugins, and tools.
MySQL is highly customizable. MS SQL Server's architecture is less flexible and can require more effort to customize.
Both databases have real strengths and weaknesses — the right choice depends on your project's specific needs.
Cross-database migration is complex and needs proper planning. Using the sample Northwind database from Microsoft as a demo, here are the three tools I tested, ranked by efficiency and performance.
It stands apart from all other tools I tested, with the fewest issues while converting from SQL Server to MySQL — only two minor default-value issues needed manual attention. The standout feature is the ability to load into existing tables, not just fresh ones, complete with column mappings. It can also synchronize source and target tables using your chosen comparison columns, or the default primary key columns, and comes with its own scheduler.


It also includes a separate command-line tool to execute saved sessions from other applications, or via Windows Task Scheduler at set intervals.
The free tool from the MySQL stable. It converts from MS SQL to MySQL using ODBC drivers — you'll need the SQL Server ODBC driver installed and an ODBC DSN created via Windows Control Panel before calling it from Workbench's Migration Wizard (Database menu → Migration Wizard).

Although it migrated tables successfully, it failed to convert views, doesn't let you load data into existing tables (let alone map columns), doesn't save migration jobs, and offers no synchronization support.

MS SQL Server ships with its own Export and Import tool, free even with Express editions — though Express editions won't let you save migration jobs. It relies on ODBC drivers; if you're running it on the same machine as MSSQL, the SQL Server ODBC driver is already installed, but you'll still need the MySQL ODBC driver from the MySQL website.

After installing the ODBC drivers, start the ODBC Administrator to create data sources: open the Start Menu, type "Data Sources" in the Run command box, then open Data Sources (ODBC).


Click the User DSN or System DSN tab and Add to choose your DSN name, ODBC driver, and connection details.
For step-by-step instructions, see How to Export Data from MSSQL Using SQL Server Management Studio (SSMS).
| Tool | Synch. Source & Target DB | Data Migration | Large DB Support | Ease of Use |
|---|---|---|---|---|
| Data Loader | Yes | Yes | Yes | High |
| MySQL Workbench | No | Yes | No | Medium |
| Import/Export Wizard | No | Yes | No | Low |
Using any of the above tools, you can successfully convert from MS SQL Server to MySQL. It's important to thoroughly test the converted database before putting it into production to ensure everything works as expected.