'Changes a column\'s SQL definition.
Note that this sqlite3 implementation ignores the ignore_constraints argument.
The argument is accepted for API compatibility with the generic
DatabaseOperations.alter_column() method.'

def alter_column(self, table_name, name, field, explicit_name=True, ignore_constraints=False):

    if ((not field.null) and field.has_default()):
        params = {'column': self.quote_name(name), 'table_name': self.quote_name(table_name)}
        self._update_nulls_to_default(params, field)
    field._suppress_default = True
    self._remake_table(table_name, altered={name: self._column_sql_for_create(table_name, name, field, explicit_name)})
