PolarDB for MySQL 8.0 is fully compatible with MySQL 5.7. You can migrate data from MySQL 5.7 databases to PolarDB for MySQL 8.0 clusters. This does not cause data loss. However, you must check the compatibility between MySQL clients and PolarDB for MySQL 8.0.
For more information about how to migrate data from MySQL 5.7 databases to PolarDB for MySQL 8.0 clusters, see the following topics:
- Create a PolarDB for MySQL cluster by migrating an ApsaraDB RDS for MySQL instance
- Migrate data from an Amazon Aurora MySQL cluster to a PolarDB for MySQL cluster
- Migrate data between PolarDB for MySQL clusters
- Migrate data from a self-managed MySQL database to a PolarDB for MySQL cluster
Client versions
You must upgrade your MySQL client to the following versions:
- Java: MySQL Connector/J 8.0 or later.
- ODBC: MySQL Connector/ODBC 8.0 or later.
- CPP: MySQL Connector/CPP 8.0 or later.
- .NET: MySQL Connector/NET 8.0 or later.
- Nodejs: MySQL Connector/Nodejs 8.0 or later.
- Python: MySQL Connector/Python 8.0.5 or later.
- Golang: go-sql-driver/mysql 1.4.0 or later.
- PHP: mysqlnd 7.4 or later.
- C/CPP: libmysqlclient 8.0 or later.
Known issues with MySQL clients
- Issue: An exception occurs when the client connects to the MySQL database. The
query_cache_size
parameter cannot be identified. - Driver version: MySQL Connector/J 5.1.42
- Database version: MySQL 8.0.13
- Solution: Use mysql-connector-java 5.1.42 or later. For more information about changelogs, see Connector/J Release Notes.
- Issue: An exception occurs when the client connects to the MySQL database. The
- Issue: The flag of
COM_STMT_EXECUTE
is invalid and theCOM_STMT_FETCH
statement is not executed to retrieve the result set. As a result, the Python driver for MySQL 8.0 fails to return the result. However, the result is returned as normal in MySQL 5.6 or MySQL 5.7. - Driver version: MySQL Connector/J 2.2.9.
- Database version: MySQL 8.0.13.
- Solution: Install the Python driver for MySQL 8.0. For more information, see Python driver.
- Issue: The flag of
- Issue: When you execute SQL statements with
kickout
on PolarDB for MySQL 8.0 clusters, the following error is returned:ERROR 1064 (42000): You have an error in your SQL syntax;
- Solution: We recommend that you upgrade the PolarDB for MySQL 8.0 cluster to the latest revision. For more information, see Upgrade the cluster version.
- Issue: When you execute SQL statements with