Drupal 7 crashing after ds_extras had been disabled and uninstalled

I've encountered the following problem:
On my 7.12 Drupal website I have had installed ds and ds_extras, but not using any features of ds (created and deleted a build mode and opened each ds admin page at most for checking features).
When using drush 5.x to disable and uninstalling the ds_extras module I got an ok message:

drush dis ds
The following extensions will be disabled: ds, ds_extras
Do you really want to continue? (y/n): y
ds was disabled successfully.                                                                                     [ok]
ds_extras was disabled successfully.                                                                              [ok]
The Display Suite module has been disabled. Any existing content that was using the Display Suite filter will now [status]
be visible in plain text. This might pose a security risk by exposing sensitive information, if any, used in the
PHP code.

drush pm-uninstall ds_extras
The following modules will be uninstalled: ds_extras
Do you really want to continue? (y/n): y
ds_extras was successfully uninstalled.                                                                           [ok]

But afterwards Drupal and drush have a serious problem and don't work anymore.
Trying to uninstall ds got me this error:

drush pm-uninstall ds
WD php: PDOException: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'revision.ds_switch' in 'field list':[error]
SELECT revision.vid AS vid, base.uid AS uid, revision.title AS title, revision.log AS log, revision.status AS
status, revision.comment AS comment, revision.promote AS promote, revision.sticky AS sticky, revision.ds_switch AS
ds_switch, base.nid AS nid, base.type AS type, base.language AS language, base.created AS created, base.changed AS
changed, base.tnid AS tnid, base.translate AS translate, revision.timestamp AS revision_timestamp, revision.uid AS
revision_uid
FROM 
{node} base
INNER JOIN {node_revision} revision ON revision.vid = base.vid
WHERE  (base.nid IN  (:db_condition_placeholder_0)) ; Array
(
    [:db_condition_placeholder_0] => 9
)
 in DrupalDefaultEntityController->load() (line 196 of
/srv/www/vhosts/<domain.tld>/httpdocs/includes/entity.inc).
Drush command terminated abnormally due to an unrecoverable error.                                                [error]
PDOException: SQLSTATE[42S22]: Column not found: 1054 Unknown column &#039;revision.ds_switch&#039; in &#039;field list&#039;: SELECT revision.vid AS vid, base.uid AS uid, revision.title AS title, revision.log AS log, revision.status AS status, revision.comment AS comment, revision.promote AS promote, revision.sticky AS sticky, revision.ds_switch AS ds_switch, base.nid AS nid, base.type AS type, base.language AS language, base.created AS created, base.changed AS changed, base.tnid AS tnid, base.translate AS translate, revision.timestamp AS revision_timestamp, revision.uid AS revision_uid
FROM 
{node} base
INNER JOIN {node_revision} revision ON revision.vid = base.vid
WHERE  (base.nid IN  (:db_condition_placeholder_0)) ; Array
(
    [:db_condition_placeholder_0] => 9
)
 in DrupalDefaultEntityController->load() (Zeile 196 von /srv/www/vhosts/<domain.tld>/httpdocs/includes/entity.inc).

But not only that, afterwards Drupal and drush constantly crash with errors, regardless of the argument or page. Drupal now always displays the following similar error:

PDOException: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'revision.ds_switch' in 'field list': SELECT revision.vid AS vid, base.uid AS uid, revision.title AS title, revision.log AS log, revision.status AS status, revision.comment AS comment, revision.promote AS promote, revision.sticky AS sticky, revision.ds_switch AS ds_switch, base.nid AS nid, base.type AS type, base.language AS language, base.created AS created, base.changed AS changed, base.tnid AS tnid, base.translate AS translate, revision.timestamp AS revision_timestamp, revision.uid AS revision_uid FROM {node} base INNER JOIN {node_revision} revision ON revision.vid = base.vid WHERE (base.nid IN (:db_condition_placeholder_0)) ; Array ( [:db_condition_placeholder_0] => 9 ) in DrupalDefaultEntityController->load() (Zeile 196 von /srv/www/vhosts/<domain.tld>/httpdocs/includes/entity.inc).

Then I tried to be witty and removed the ds module directory, but drush and Drupal didn't recover. Drush still gives the same error and Drupal now adds two warnings upfront which seem not to be ds related (at least on the first glance, I've no dug deeper):

Notice: Undefined variable: navigation in include() (Zeile 52 von /srv/www/vhosts/<domain.tld>/httpdocs/sites/all/themes/zen/templates/maintenance-page.tpl.php).
    Notice: Undefined variable: navigation in include() (Zeile 67 von /srv/www/vhosts/<domain.tld>/httpdocs/sites/all/themes/zen/templates/maintenance-page.tpl.php).
    PDOException: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'revision.ds_switch' in 'field list': SELECT revision.vid AS vid, base.uid AS uid, revision.title AS title, revision.log AS log, revision.status AS status, revision.comment AS comment, revision.promote AS promote, revision.sticky AS sticky, revision.ds_switch AS ds_switch, base.nid AS nid, base.type AS type, base.language AS language, base.created AS created, base.changed AS changed, base.tnid AS tnid, base.translate AS translate, revision.timestamp AS revision_timestamp, revision.uid AS revision_uid FROM {node} base INNER JOIN {node_revision} revision ON revision.vid = base.vid WHERE (base.nid IN (:db_condition_placeholder_0)) ; Array ( [:db_condition_placeholder_0] => 9 ) in DrupalDefaultEntityController->load() (Zeile 196 von /srv/www/vhosts/<domain.tld>/httpdocs/includes/entity.inc).

So, it seems ds_extras uninstall didn't remove everything, something in the Drupal default entity controller has been left behind.

So, what steps did I wrong? Should i have left ds enabled for the first uninstallation? But there was no error stated in uninstalling ds_extras.

Maybe the uninstalling hook of ds_extras needs to be enhanced to remove the problematic db content or don't allow uninstalling when ds is disabled already?

I wonder what damage ds/ds_extras can do to the Drupal core database so that Drupal will not recover to work when ds/ds_extras are disabled and removed. It seems to me that Drupal core (entity controller) would need to have some recovering code in such cases, at least when related modules are disabled, but that is probably only wishful thinking, as I have not dug deep enough into the Drupal architecture to know.

Br,
meichr.