备份rake db迁移。 和命令拒绝rake db：migrate rake中止

Question

I have db version 11. I want to move back to version 10 and add another version. But before that I want to take backup of version 11. How can I do that? I am using ruby 1.8.7 and rails 1.2.6.

rake db:migrate version=10

output: rake aborted! ActiveREcord::StatementInvalid: Mysql::Error SELECT command denied to user ''@'%' for column slot in table 'users' rake aborted! ActiveREcord::StatementInvalid: Mysql::Error SELECT command denied to user ''@'%' for column slot in table 'users'

Any help ?

Answer 1

That's a mighty old version of Rails you're using there!

You want to run a down migration to go back to a previous version:

rake db:migrate:down version=10

To make a backup first, use the client utility for your database. For example, with MySQL:

mysqldump -u username -p databasename > dumpfile.sql