method
change_column_default
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change_column_default(table_name, column_name, default)
public
Sets a new default value for a column.
Examples
change_column_default(:suppliers, :qualification, 'new') change_column_default(:accounts, :authorized, 1) change_column_default(:users, :email, nil)
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mutru -
October 10, 2008
Vidmantas -
July 30, 2009
Vidmantas -
October 10, 2008 - (v2.1.0)
meritize -
July 20, 2014
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8 thanks
Implemented in database adapters
These methods are not implemented in the abstract classes. Instead, all database adapters implement these separately, if the feature is supported.
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2 thanks
How to set default value to NULL
To set default value to NULL you can use change_column method instead, for example:
change_column :suppliers, :qualification, :string, :default => nil
Just make sure you don’t change data type accidentally ;-)
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1 thank
Not implented yet
According to this method’s source, change_column_default is not implemented as well as change_column
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0 thanks
change_column did the trick for me
Use change_column, and make sure to specify the datatype:
class ChangeUsers < ActiveRecord::Migration def up change_column :users, :is_vote_reminder, :boolean, :default => true end end