In today’s data management world, data migration is a common task as business requirements and technical environments change. One of the common scenarios is migrating a MySQL database to SQL Server, which may stem from system upgrades, business integration, performance optimization, or platform strategy adjustments.
The purpose of this article is to provide an in-depth overview of the two main approaches on how to migrate MySQL to SQL Server successfully and discuss the considerations involved.
What is MySQL and SQL Server
MySQL is an open-source relational database management system that is widely popular for its flexibility, high availability, and cost-effectiveness. Microsoft SQL Server, on the other hand, is a commercial relational database management system developed by Microsoft Corporation with excellent performance and strong enterprise-level feature support, especially in Windows environment.
Why Migrate MySQL to SQL Server
When an organization makes heavy use of Microsoft’s technology stack internally, migrating MySQL to SQL Server allows for better and seamless integration with Microsoft products such as Azure cloud services, Power BI, and more.
SQL Server offers better performance in certain scenarios, especially in massively concurrent processing, OLAP analytics, and complex transactions.
SQL Server is equipped with a wealth of advanced security features and compliance tools, such as AlwaysOn High Availability solution, Transparent Data Encryption (TDE), etc., to meet the higher requirements of enterprises for data security and stability.
These are the reasons why need to migrate MySQL to SQL Server.
Pre-migration Assessment and Planning
Before you migrate MySQL to SQL Server, you are supposed to finish checking the following points.
Determine the target architecture and version for migration and check for compatibility issues between the source MySQL database and the target SQL Server.
Conduct a comprehensive audit of the source database to understand the details of table structures, indexes, stored procedures, triggers, views, and other objects.
Evaluate the data volume size, inter-table relationships, and potential data conversion needs.
Using SQL Server Migration Assistant for MySQL (SSMA)
Use a specialized migration tool such as SQL Server Migration Assistant for MySQL (SSMA) provided by Microsoft, which automatically converts MySQL database objects and migrates data.
The detailed steps to migrate MySQL to SQL Server using SQL Server Migration Assistant for MySQL (SSMA) are listed below:
Step 1: Install and Start SSMA for MySQL
Visit Microsoft official website to download the latest version of SSMA for MySQL tool. Install SSMA, follow the prompts to proceed with the installation process and make sure that the system requirements are met (e.g. .NET Framework, etc.). After the installation is complete, launch the SQL Server Migration Assistant for MySQL application.
Step 2: Create A New Project
In SSMA, click “File” menu, select “New Project” or directly click the New Project icon on the upper left corner. Set the project name and target SQL Server version information, such as SQL Server 2019 or Azure SQL Database. Determine the conversion rules and global settings, such as data type mapping, object name handling, etc.
Step 3: Connect to MySQL Source Database
In the SSMA interface, click the Connect to MySQL button. Provide the MySQL server address, port, database name, username, and password to establish a connection to the MySQL database. After a successful connection, the tables, views, stored procedures, etc. in the MySQL database will be listed in the metadata browser on the left.
Step 4: Convert MySQL Schema
In the Metadata Browser, select the database or specific objects (e.g. tables, stored procedures, etc.) that need to be migrated. Right-click and select “Convert Schema” or use the corresponding option in the top menu bar to start the conversion process. SSMA will analyze and convert MySQL database objects to SQL Server compatible T-SQL scripts.
Step 5: Load Converted Schema to SQL Server
Connect to the target SQL Server instance in SSMA. Load the converted T-SQL scripts to SQL Server, either by generating the scripts and executing them manually or by executing them directly in SSMA to create the new database structure.
Step 6: Migrate Data
Select the MySQL database or specific table that has been successfully converted. Click the “Migrate Data” button or right-click and select “Migrate Data to SQL Server” to start the data migration process. Configure the migration options, such as batch size, error handling policy, etc. according to the actual situation.
Start to migrate data. During this process, SSMA will migrate the data from MySQL to the corresponding tables in SQL Server.
Step 7: Verification and Testing
After the data migration is complete, verify in SQL Server that the table structure and data are migrated correctly. Test the related applications to ensure that they work properly in the new SQL Server environment.
Note: During the migration process, you may need to deal with issues such as incompatible data types, logical differences in triggers and stored procedures, etc. Ensure that these issues are resolved during the conversion phase. It is recommended to perform a full migration walkthrough in a test environment before formal migration to minimize risks in the production environment.
Migration Manually or by Scripting
You could also manually migrate MySQL to SQL Server. Export MySQL data to an intermediate format (e.g. CSV, XML) manually or by scripting and then import it into SQL Server.
The specific steps are as follows:
Step 1: Export MySQL Data to CSV
For each table to be migrated, you can use the SELECT INTO OUTFILE command to export the data to CSV format:
sql
— Execute the following command in MySQL
SELECT * FROM your_table
INTO OUTFILE ‘/path/to/your_table.csv’
FIELDS TERMINATED BY ‘,’
ENCLOSED BY ‘”‘
LINES TERMINATED BY ‘\n’.
Step 2: Convert Special Characters and Data Types
As needed, it may be necessary to handle the formatting of date-time fields and other special data types to ensure that they are in a format that is properly recognized by SQL Server in the CSV file. You can proceed directly to Step 3 if not required.
Step 3: Create SQL Server Target Table Structure
First, you need to create tables in SQL Server that match the MySQL table structure. This step can be done during the manual migration of the database structure phase mentioned above or can be created separately.
Step 4: Import CSV Data to SQL Server
Use SQL Server Management Studio (SSMS) or the bcp command line tool to import CSV data into SQL Server tables.
For example, in SSMS:
- Right click the target table -> select “Task” -> “Import Data”.
- In the Data Import Wizard, select the source data source as “Flat File Source” and specify the location of the CSV file you just exported.
- Set the column mapping and data format options to ensure that the data is imported correctly.
- Or use the bcp command line tool (you need to create the appropriate format file first):
bcp YourDatabase.dbo.YourTable in /path/to/your_table.csv -S [server_name] -U [username] -P [password] -c -t , -T
Note: Make sure that the order of columns in the CSV file matches the order of columns in the SQL Server table, or explicitly specify the column mapping during import. Handle data that contains special characters such as commas to avoid errors during import.
If there are self-incrementing primary keys or other specific constraints in the table, please set up the correct primary key policy or disable the related constraints before importing, and re-enable them after the import is completed.
This method is suitable for scenarios with small amount of data and low performance requirements. For large databases, it will be more efficient and convenient to use professional migration tools (such as SQL Server Migration Assistant for MySQL) directly.
Conclusion
To migrate MySQL to SQL Server is a complex project that involves database design, data conversion, performance tuning and business continuity. With professional migration tools and services, combined with a detailed planning and validation process, you can ensure the successful implementation of the migration to the greatest extent possible.
During the entire migration process, full consideration of compatibility, security, performance, and other factors, as well as adequate backup and recovery plans, is the key to ensuring the smooth progress of the project.
At the same time, continuous monitoring and optimization of the performance of the migrated SQL Server database is the only way to give full play to its advantages and meet the long-term development needs of the enterprise.