Effective way to migrate from SQL Server to MySQL
If you're looking for an easy-to-use, open-sourced tool, checkout etlalchemy.

You can carry out your SQL Server to MySQL database migration with 4 lines of Python code:

To Install: 

pip install etlalchemy


(On El Capitan you may have to run pip install --ignore-installed etlalchemy)

To Run:

from etlalchemy import ETLAlchemySource, ETLAlchemyTarget

mssql_db_source = ETLAlchemySource("mssql+pyodbc://username:password@DSN_NAME")

mysql_db_target = ETLAlchemyTarget("mysql://username:password@hostname/db_name", 
              drop_database=True)

mysql_db_target.addSource(mssql_db_source)
mysql_db_target.migrate()


If you want to learn more about etlalchemy, check out this article.