18    if op.get_context().bind.dialect.name != 
'postgresql':
 
   19        if op.get_context().bind.dialect.name == 
'mssql':
 
   20            op.drop_constraint(
'ck_ps_endpoints_identify_by_pjsip_identify_by_values',
 
   22        op.alter_column(table_name, column_name, type_=sa.String(80))
 
   26    op.execute(
'ALTER TABLE ' + table_name + 
' ALTER COLUMN ' + column_name +
 
   27               ' TYPE varchar(80) USING identify_by::text::' + enum_name)
 
   29    op.execute(
'DROP TYPE ' + enum_name)
 
 
   33    if op.get_context().bind.dialect.name != 
'postgresql':
 
   34        op.alter_column(table_name, column_name,
 
   35                        type_=sa.Enum(*enum_values, name=enum_name))
 
   39    updated = sa.Enum(*enum_values, name=enum_name)
 
   40    updated.create(op.get_bind(), checkfirst=
False)
 
   42    op.execute(
'ALTER TABLE ' + table_name + 
' ALTER COLUMN ' + column_name +
 
   43               ' TYPE ' + enum_name + 
' USING identify_by::text::' + enum_name)