Question

我在HyperRecord的前端使用Hypertable db。我修复了一些错误。但现在迁移让我感到困惑。我什么时候迁移它会显示错误：

rake aborted!
undefined method `select_rows' for #<ActiveRecord::ConnectionAdapters::HypertableAdapter:0xb6f791c4>
.rvm/gems/ruby-1.8.7-p352@r2.3.8/gems/activerecord-2.3.8/lib/active_record/connection_adapters/abstract/database_statements.rb:27:in `select_values'

当我查看rails actice_record上的代码或ruby时。它显示了。

  # Returns an array of arrays containing the field values.
  # Order is the same as that returned by +columns+.
  def select_rows(sql, name = nil)
  end
  undef_method :select_rows

我尝试通过在初始化中添加修复来删除这些功能。

module ActiveRecord
  module ConnectionAdapters
    class HypertableAdapter

      def select_rows(sql, name = nil)
      end
    end
  end
end

然后出现错误Nil value occurred while accepting array or hash。为了解决这个问题，我在修复代码中添加了新方法。

module ActiveRecord
  module ConnectionAdapters
    class HypertableAdapter

      def select_rows(sql, name = nil)
      end

      def select_values(sql, name = nil)
        result = select_rows(sql, name)
        result.map { |v| v[0] } unless result.nil?
      end
    end
  end
end

然后它出现了错误：

rake aborted!
You have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occurred while evaluating nil.map
/.rvm/gems/ruby-1.8.7-p352@r2.3.8/gems/activerecord-2.3.8/lib/active_record/migration.rb:421:in `get_all_versions'

有没有人有想法，发生了什么事？

Answer 1

此代码删除所有错误。但现在迁移运行良好，但不会回滚。

module ActiveRecord
  module ConnectionAdapters
    class HypertableAdapter

      def select_rows(sql, name = nil)
        result = execute(sql)
        rows = []
        result.cells.each { |row| rows << row }
        rows
      end

      def select_values(sql, name = nil)
        result = select_rows(sql, name)
        result.map { |v| v[0] } unless result.nil?
      end
    end
  end
end

当我检查架构文件时，它显示以下错误：

# Could not dump table "teams" because of following StandardError
#   Unknown type '' for column 'ROW'

导致问题的高速移动导致导轨2.3.8

1 个答案: