107    for table_name, column_list 
in itertools.groupby(COLUMNS, operator.itemgetter(0)):
 
  108        with op.batch_alter_table(table_name) 
as batch_op:
 
  109            for _, column_name 
in column_list:
 
  110                batch_op.alter_column(column_name,
 
  111                                      type_=ast_bool_values,
 
  112                                      existing_type=yesno_values,
 
  113                                      postgresql_using=
'"{}"::text::{}'.format(column_name, AST_BOOL_NAME))
 
 
  116    for table_name, column_list 
in itertools.groupby(COLUMNS, operator.itemgetter(0)):
 
  117        subject = table(table_name)
 
  119        for _, column_name 
in column_list:
 
  120            subject.append_column(column(column_name))
 
  121            values_exprs[column_name] = cast(
 
  122                case((or_(subject.c[column_name] == text(
"'yes'"),
 
  123                          subject.c[column_name] == text(
"'1'"),
 
  124                          subject.c[column_name] == text(
"'on'"),
 
  125                          subject.c[column_name] == text(
"'true'")), text(
"'yes'")),
 
  130            subject.update().
values(values_exprs)
 
  133    for table_name, column_list 
in itertools.groupby(COLUMNS, operator.itemgetter(0)):
 
  134        with op.batch_alter_table(table_name) 
as batch_op:
 
  135            for _, column_name 
in column_list:
 
  136                batch_op.alter_column(column_name,
 
  138                                      existing_type=ast_bool_values,
 
  139                                      postgresql_using=
'"{}"::text::{}'.format(column_name, YESNO_NAME))