Migrating from MySQL to SQL Server involves transferring your database schema, data, and any relevant application code from the MySQL database to a SQL Server database. This whitepaper explores the migration process and contains some hints on choosing MySQL to MS SQL converter.
Here are the general steps required for the database migration:
- Assess MySQL database: Understand the size, complexity, and dependencies of the source MySQL database. Identify any features or functionalities that are specific to MySQL and might require adjustments when migrating to SQL Server.
- Plan the migration: Create a migration plan that outlines the timeline, resources, and steps involved in the MySQL to MS SQL migration. Consider factors like data volume, downtime restrictions, and potential risks. Plan a maintenance window or downtime period to switch the production environment from MySQL to SQL Server.
- Set up the SQL Server or Azure SQL environment: Install and configure SQL Server on the target server or Azure SQL cloud. Make sure you have the necessary permissions and access grants on MySQL and MS SQL servers to perform the migration.
- Schema migration: Convert the database schema, tables, views, stored procedures, functions, and any other MySQL database objects to SQL Server or Azure SQL with respect to correct type mapping and handling keywords. Ensure that the datatypes, constraints, and indexes are compatible with SQL Server.
- Data migration: Transfer the data from MySQL to SQL Server. You can use several methods for this, such as using the SQL Server Migration Assistant (SSMA), writing scripts, or using data integration tools. Perform thorough testing to verify data integrity and consistency.
- Code migration: If you have application code that interacts with the database, review and modify any SQL queries or statements that are specific to MySQL syntax or behavior. Ensure that the code is compatible with SQL Server paying special attention to translating built-in functions.
- Testing and validation: Perform comprehensive testing to verify the functionality, performance, and accuracy of the migrated MS SQL database. Test various scenarios, including data retrieval, data manipulation, and application workflows.
- Application Layer: Update the application configurations, connection strings, and any other relevant settings to point to the new SQL Server database.
- Post-migration tasks: After the migration, monitor the SQL Server environment for any issues, performance bottlenecks, or errors. Optimize the database if needed and update any necessary documentation.
MySQL and MS SQL have similar types and most of them are equal. The table below contains distinguished data types requiring special attention when convert MySQL to MS SQL:
|YEAR[(2 | 4)]||NUMERIC(4)|
MySQL field property AUTO_INCREMENT must be converted into MS SQL IDENTITY.
One of the top challenges when running MySQL to MS SQL database migration is conversion of SQL code in views, stores procedures, functions and triggers.
MySQL limited queries ‘SELECT … LIMIT number_of_rows’ must be converted into ‘SELECT TOP number_of_rows …’ MS SQL.
Unlike MySQL, SQL Server and Azure SQL requires all selected columns in ‘SELECT … GROUP BY …’ queries to be either under ‘GROUP BY’ clause or in aggregation functions.
Specific MySQL built-in functions must be replaced by MS SQL equivalents according to the table below:
|CONCAT($arg1, $arg2, …)||$arg1 + $arg2 + …|
|curdate(), CURRENT_DATE||CAST(getdate() AS date)|
|curtime(),CURRENT_TIME||CAST(getdate() AS time)|
|isnull($expression)||$expression is null|
|$expr like $temmplate||CONTAINS($expr, $template)|
|timediff($date1, $date2)||CAST($date1 – $date2 AS TIME)|
As you can see from the guide above, database migration from MySQL to MS SQL is not a trivial task. There are some useful software tools that could help automate most steps of the migration.
First above all, it is Microsoft SQL Server Migration Assistant (SSMA) for MySQL. This is a tool assisting in migration of MySQL databases to any version of SQL Server starting from 2012 including Azure SQL. It provides a collection of tools to perform the following steps:
- Establish connection to the source MySQL database
- Establish connection to an instance of MS SQL or Azure SQL database
- Migrate MySQL database entries (metadata) to SQL Server or Azure SQL equivalents
- Load the resulting entries into SQL Server or Azure SQL database
- Migrate MySQL data to SQL Server or Azure SQL
Install and Connect. Download and install the latest version of SSMA for MySQL from the official Microsoft website. Create a New SSMA Project: Launch the SSMA tool and create a new project by clicking on “File” > “New Project”. In the SSMA project window, right-click on “Connect to MySQL” and enter the connection details for your MySQL database, including server name, port, username, and password. Click “Connect” to establish the connection.
Configure. After connection is established, it is time to configure SSMA for MySQL conversion settings. In the project window, click on “Project Settings” to configure the conversion settings. Here, you can specify options related to data type mapping, schema and object conversion, and other migration preferences. Review and modify these settings as per your requirements.
Migrate Schemas. First, convert all the necessary MySQL schemas into MS SQL or Azure SQL format. Right-click on the MySQL database and choose “Convert Schema”. This step converts the MySQL schema objects to their corresponding MS SQL format based on the configured conversion settings. After the schema conversion, review the conversion report to identify any issues or warnings. Address them by manually modifying the schema or adjusting the conversion settings accordingly.
Migrate Data. Right-click on the MySQL database and select “Migrate Data”. This step migrates the data from the MySQL tables to the corresponding MS SQL tables. SSMA provides options to migrate all data or specify a subset of data based on filtering criteria. Once the data migration is complete, verify the integrity and consistency of the migrated data in MS SQL. Perform thorough testing to ensure the migrated database functions as expected.
Although SSMA for MySQL essentially simplifies the database migration, it still requires a lot of actions to configure and run the process. For those who look for completely automated solution, it is recommend to consider commercial MySQL to SQL Server converters since these tools are specially designed to launch any kind of complicated migration with just a few button-clicks. One of such tools is MySQL to MS SQL converter developed by Intelligent Converters software vendor.
Key features of MySQL to MS SQL converter:
- All modern versions of MySQL and SQL Server are supported including forks and DBaaS variations (Azure SQL, Amazon RDS, etc)
- Schemas, data, indexes, constraints, foreign keys and views are converted
- High performance of the data migration due to bulk reading and writing techniques
- Option to modify name, type and other properties of every column and exclude particular columns from migration
- Option to convert MySQL database into T-SQL script file (for those cases when direct connection to the target DBMS is not available)
- Option to merge and synchronize existing MS SQL or Azure SQL database with MySQL data
- Option to filter data for conversion and combine multiple tables in a single one using SELECT-queries
Visit official site of Intelligent Converters for more information about the product.