Incompatibility between mysqldump and an alternative DBMS

Symptoms

When creating a backup, a compatibility error between mysqldump and the alternate database occurs. The following error is registered in the log at /usr/local/mgr5/var/backup2_system.log:

WARNING Cant backup db what: Failed to back up the database. Error: ‘mysqldump: Couldn’t execute ‘select column_name, extra, generation_expression, data_type from information_schema.columns where table_schema=database() and table_name=‘vb_aaggregate_temp_1384809000’ order by ordinal_position’: Unknown column ‘generation_expression’ in ‘field list’ (1054)

Solution

Create a database dump manually using the following command:

docker exec -it containername bash -c 'mysqldump dbname > /etc/mysql/conf.d/dbname.sql'

The dump file will be available outside the container in the /etc/ispmysql/containername/ directory.

For example, for an alternative database named dbname from MySQL 5.5, the command would be:

docker exec -it mysql-5.5 bash -c 'mysqldump dbname > /etc/mysql/conf.d/dbname.sql'

The dump file would be located at /etc/ispmysql/mysql-5.5/.