method
change_null
rails latest stable - Class:
ActiveRecord::ConnectionAdapters::ColumnMethods::Table
change_null(column_name, null, default = nil)public
Sets or removes a NOT NULL constraint on a column.
t.change_null(:qualification, true) t.change_null(:qualification, false, 0)
See {connection.change_column_null}[rdoc-ref:SchemaStatements#change_column_null]