I’m always looking for those somewhere on web when I need them. Now I’m posting them here so I will always have them handy. If you need them then you can use this as a reference. Below is a list of supported types with its MySQL representation.

• :primary_key – int(11) DEFAULT NULL auto_increment PRIMARY KEY
• :string – varchar(255)
• :text – text
• :integer – int limit 4
• :float – float
• :decimal – decimal
• :datetime – datetime
• :timestamp – datetime
• :time – time
• :date – date
• :binary – blob
• :boolean – tinyint(1)

It can also be found in this constant in ActiveRecord ConnectionAdapters MysqlAdapter

ActiveRecord::ConnectionAdapters::MysqlAdapter.NATIVE_DATABASE_TYPES

I think that all the other type mappings could be found in appropriate ActiveRecord Connection adapters.

Cheers, Gregster