After upgrading to drupal 6.9 Views with "Distinct option" activated doesn't work

If I deactivate the Distinct Flag it works.

View definition:

$view = new view;
$view->name = 'clientes';
$view->description = 'Lista de clientes';
$view->tag = 'clientes';
$view->view_php = '';
$view->base_table = 'node';
$view->is_cacheable = FALSE;
$view->api_version = 2;
$view->disabled = FALSE; /* Edit this to true to make a default view disabled initially */
$handler = $view->new_display('default', 'Lista clientes', 'default');
$handler->override_option('fields', array(
  'title' => array(
    'label' => 'Nombre',
    'link_to_node' => 1,
    'exclude' => 0,
    'id' => 'title',
    'table' => 'node',
    'field' => 'title',
    'relationship' => 'none',
  ),
  'field_representante_uid' => array(
    'label' => 'representante',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_representante_uid',
    'table' => 'node_data_field_representante',
    'field' => 'field_representante_uid',
    'relationship' => 'none',
  ),
  'field_canal_venta_value' => array(
    'label' => 'Canal de venta',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_canal_venta_value',
    'table' => 'node_data_field_canal_venta',
    'field' => 'field_canal_venta_value',
    'relationship' => 'none',
  ),
  'field_email_email' => array(
    'label' => 'Email',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_email_email',
    'table' => 'node_data_field_email',
    'field' => 'field_email_email',
    'relationship' => 'none',
  ),
  'field_fax_value' => array(
    'label' => 'Fax',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_fax_value',
    'table' => 'node_data_field_fax',
    'field' => 'field_fax_value',
    'relationship' => 'none',
  ),
  'field_persona_contacto_value' => array(
    'label' => 'Persona de contacto',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_persona_contacto_value',
    'table' => 'node_data_field_persona_contacto',
    'field' => 'field_persona_contacto_value',
    'relationship' => 'none',
  ),
  'field_url_url' => array(
    'label' => 'Página web',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_url_url',
    'table' => 'node_data_field_url',
    'field' => 'field_url_url',
    'relationship' => 'none',
  ),
  'field_telefono_value' => array(
    'label' => 'Teléfono',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_telefono_value',
    'table' => 'node_data_field_telefono',
    'field' => 'field_telefono_value',
    'relationship' => 'none',
  ),
));
$handler->override_option('filters', array(
  'type' => array(
    'operator' => 'in',
    'value' => array(
      'cliente' => 'cliente',
    ),
    'group' => '0',
    'exposed' => FALSE,
    'expose' => array(
      'operator' => FALSE,
      'label' => '',
    ),
    'id' => 'type',
    'table' => 'node',
    'field' => 'type',
    'relationship' => 'none',
  ),
  'field_representante_uid' => array(
    'operator' => 'or',
    'value' => array(),
    'group' => '0',
    'exposed' => TRUE,
    'expose' => array(
      'use_operator' => 0,
      'operator' => 'field_representante_uid_op',
      'identifier' => 'field_representante_uid',
      'label' => 'Representante',
      'optional' => 1,
      'single' => 1,
      'remember' => 0,
      'reduce' => 0,
    ),
    'id' => 'field_representante_uid',
    'table' => 'node_data_field_representante',
    'field' => 'field_representante_uid',
    'relationship' => 'none',
    'reduce_duplicates' => 0,
    'override' => array(
      'button' => 'Override',
    ),
  ),
  'field_canal_venta_value_many_to_one' => array(
    'operator' => 'or',
    'value' => array(),
    'group' => '0',
    'exposed' => TRUE,
    'expose' => array(
      'use_operator' => 0,
      'operator' => 'field_canal_venta_value_many_to_one_op',
      'identifier' => 'field_canal_venta_value_many_to_one',
      'label' => 'Canal de venta',
      'optional' => 1,
      'single' => 0,
      'remember' => 0,
      'reduce' => 0,
    ),
    'id' => 'field_canal_venta_value_many_to_one',
    'table' => 'node_data_field_canal_venta',
    'field' => 'field_canal_venta_value_many_to_one',
    'relationship' => 'none',
    'reduce_duplicates' => 1,
    'override' => array(
      'button' => 'Override',
    ),
  ),
));
$handler->override_option('access', array(
  'type' => 'perm',
  'perm' => 'access content',
));
$handler->override_option('title', 'Lista de clientes');
$handler->override_option('use_ajax', TRUE);
$handler->override_option('items_per_page', 20);
$handler->override_option('use_pager', 'mini');
$handler->override_option('use_more', 1);
$handler->override_option('distinct', 1);
$handler->override_option('style_plugin', 'table');
$handler->override_option('style_options', array(
  'grouping' => '',
  'override' => 1,
  'sticky' => 1,
  'order' => 'asc',
  'columns' => array(
    'title' => 'title',
    'field_canal_venta_value' => 'field_canal_venta_value',
    'field_email_email' => 'field_email_email',
    'field_fax_value' => 'field_fax_value',
    'field_persona_contacto_value' => 'field_persona_contacto_value',
    'field_url_url' => 'field_url_url',
    'field_telefono_value' => 'field_telefono_value',
  ),
  'info' => array(
    'title' => array(
      'sortable' => 1,
      'separator' => '',
    ),
    'field_canal_venta_value' => array(
      'sortable' => 1,
      'separator' => '',
    ),
    'field_email_email' => array(
      'sortable' => 1,
      'separator' => '',
    ),
    'field_fax_value' => array(
      'sortable' => 1,
      'separator' => '',
    ),
    'field_persona_contacto_value' => array(
      'sortable' => 1,
      'separator' => '',
    ),
    'field_url_url' => array(
      'sortable' => 1,
      'separator' => '',
    ),
    'field_telefono_value' => array(
      'sortable' => 1,
      'separator' => '',
    ),
  ),
  'default' => 'title',
));
$handler->override_option('exposed_block', TRUE);
$handler = $view->new_display('page', 'Página todos los clientes', 'page_1');
$handler->override_option('path', 'clientes');
$handler->override_option('menu', array(
  'type' => 'normal',
  'title' => 'Clientes',
  'weight' => '-1',
  'name' => 'primary-links',
));
$handler->override_option('tab_options', array(
  'type' => 'none',
  'title' => '',
  'weight' => 0,
));
$handler = $view->new_display('page', 'Página de clientes de un comercial', 'page_2');
$handler->override_option('fields', array(
  'title' => array(
    'label' => 'Nombre',
    'link_to_node' => 1,
    'exclude' => 0,
    'id' => 'title',
    'table' => 'node',
    'field' => 'title',
    'relationship' => 'none',
  ),
  'field_representante_uid' => array(
    'label' => 'representante',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 1,
    'id' => 'field_representante_uid',
    'table' => 'node_data_field_representante',
    'field' => 'field_representante_uid',
    'relationship' => 'none',
    'override' => array(
      'button' => 'Use default',
    ),
  ),
  'field_canal_venta_value' => array(
    'label' => 'Canal de venta',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_canal_venta_value',
    'table' => 'node_data_field_canal_venta',
    'field' => 'field_canal_venta_value',
    'relationship' => 'none',
  ),
  'field_email_email' => array(
    'label' => 'Email',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_email_email',
    'table' => 'node_data_field_email',
    'field' => 'field_email_email',
    'relationship' => 'none',
  ),
  'field_fax_value' => array(
    'label' => 'Fax',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_fax_value',
    'table' => 'node_data_field_fax',
    'field' => 'field_fax_value',
    'relationship' => 'none',
  ),
  'field_persona_contacto_value' => array(
    'label' => 'Persona de contacto',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_persona_contacto_value',
    'table' => 'node_data_field_persona_contacto',
    'field' => 'field_persona_contacto_value',
    'relationship' => 'none',
  ),
  'field_url_url' => array(
    'label' => 'Página web',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_url_url',
    'table' => 'node_data_field_url',
    'field' => 'field_url_url',
    'relationship' => 'none',
  ),
  'field_telefono_value' => array(
    'label' => 'Teléfono',
    'link_to_node' => 0,
    'label_type' => 'widget',
    'format' => 'default',
    'multiple' => array(
      'group' => TRUE,
      'multiple_number' => '',
      'multiple_from' => '',
      'multiple_reversed' => FALSE,
    ),
    'exclude' => 0,
    'id' => 'field_telefono_value',
    'table' => 'node_data_field_telefono',
    'field' => 'field_telefono_value',
    'relationship' => 'none',
  ),
));
$handler->override_option('arguments', array(
  'field_representante_uid' => array(
    'default_action' => 'not found',
    'style_plugin' => 'default_summary',
    'style_options' => array(),
    'wildcard' => 'all',
    'wildcard_substitution' => 'Todos',
    'title' => '',
    'default_argument_type' => 'fixed',
    'default_argument' => '',
    'validate_type' => 'none',
    'validate_fail' => 'not found',
    'break_phrase' => 0,
    'not' => 0,
    'id' => 'field_representante_uid',
    'table' => 'node_data_field_representante',
    'field' => 'field_representante_uid',
    'override' => array(
      'button' => 'Use default',
    ),
    'relationship' => 'none',
    'default_options_div_prefix' => '',
    'default_argument_user' => 0,
    'default_argument_fixed' => '',
    'default_argument_php' => '',
    'validate_argument_node_type' => array(
      'cliente' => 0,
      'page' => 0,
      'story' => 0,
      'visita' => 0,
    ),
    'validate_argument_node_access' => 0,
    'validate_argument_nid_type' => 'nid',
    'validate_argument_vocabulary' => array(),
    'validate_argument_type' => 'tid',
    'validate_argument_php' => '',
  ),
));
$handler->override_option('filters', array(
  'type' => array(
    'operator' => 'in',
    'value' => array(
      'cliente' => 'cliente',
    ),
    'group' => '0',
    'exposed' => FALSE,
    'expose' => array(
      'operator' => FALSE,
      'label' => '',
    ),
    'id' => 'type',
    'table' => 'node',
    'field' => 'type',
    'relationship' => 'none',
  ),
  'field_representante_uid' => array(
    'operator' => 'or',
    'value' => array(),
    'group' => '0',
    'exposed' => FALSE,
    'expose' => array(
      'operator' => 'field_representante_uid_op',
      'label' => 'Representante',
      'use_operator' => 0,
      'identifier' => 'field_representante_uid',
      'optional' => 1,
      'single' => 1,
      'remember' => 0,
      'reduce' => 0,
    ),
    'id' => 'field_representante_uid',
    'table' => 'node_data_field_representante',
    'field' => 'field_representante_uid',
    'relationship' => 'none',
    'reduce_duplicates' => 0,
    'override' => array(
      'button' => 'Use default',
    ),
  ),
  'field_canal_venta_value_many_to_one' => array(
    'operator' => 'or',
    'value' => array(),
    'group' => '0',
    'exposed' => TRUE,
    'expose' => array(
      'use_operator' => 0,
      'operator' => 'field_canal_venta_value_many_to_one_op',
      'identifier' => 'field_canal_venta_value_many_to_one',
      'label' => 'Canal de venta',
      'optional' => 1,
      'single' => 0,
      'remember' => 0,
      'reduce' => 0,
    ),
    'id' => 'field_canal_venta_value_many_to_one',
    'table' => 'node_data_field_canal_venta',
    'field' => 'field_canal_venta_value_many_to_one',
    'relationship' => 'none',
    'reduce_duplicates' => 1,
    'override' => array(
      'button' => 'Override',
    ),
  ),
));
$handler->override_option('title', 'Clientes de %1');
$handler->override_option('path', 'user/%/clientes');
$handler->override_option('menu', array(
  'type' => 'tab',
  'title' => 'Clientes asignados',
  'weight' => '-1',
  'name' => 'navigation',
));
$handler->override_option('tab_options', array(
  'type' => 'none',
  'title' => '',
  'weight' => 0,
));

Live Preview SQL Query:

SELECT DISTINCT(node.nid) AS nid,
   node.title AS node_title,
   node_data_field_representante.field_representante_uid AS node_data_field_representante_field_representante_uid,
   node_data_field_representante.nid AS node_data_field_representante_nid,
   node.type AS node_type,
   node_data_field_representante.field_canal_venta_value AS node_data_field_representante_field_canal_venta_value,
   node_data_field_representante.field_email_email AS node_data_field_representante_field_email_email,
   node_data_field_representante.field_fax_value AS node_data_field_representante_field_fax_value,
   node_data_field_representante.field_persona_contacto_value AS node_data_field_representante_field_persona_contacto_value,
   node_data_field_representante.field_url_url AS node_data_field_representante_field_url_url,
   node_data_field_representante.field_url_title AS node_data_field_representante_field_url_title,
   node_data_field_representante.field_url_attributes AS node_data_field_representante_field_url_attributes,
   node_data_field_representante.field_telefono_value AS node_data_field_representante_field_telefono_value
 FROM node node 
 LEFT JOIN content_type_cliente node_data_field_representante ON node.vid = node_data_field_representante.vid
 WHERE node.type in ('cliente')
   ORDER BY node_title ASC

Real SQL Query with error:

    * user warning: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DISTINCT(node.nid), node.title AS node_title, node_data_field_representant' at line 1 query: SELECT COUNT(*) FROM (SELECT DISTINCT(node.nid) AS DISTINCT(node.nid), node.title AS node_title, node_data_field_representante.field_representante_uid AS node_data_field_representante_field_representante_uid, node_data_field_representante.nid AS node_data_field_representante_nid, node.type AS node_type, node_data_field_representante.field_canal_venta_value AS node_data_field_representante_field_canal_venta_value, node_data_field_representante.field_email_email AS node_data_field_representante_field_email_email, node_data_field_representante.field_fax_value AS node_data_field_representante_field_fax_value, node_data_field_representante.field_persona_contacto_value AS node_data_field_representante_field_persona_contacto_value, node_data_field_representante.field_url_url AS node_data_field_representante_field_url_url, node_data_field_representante.field_url_title AS node_data_field_representante_field_url_title, node_data_field_representante.field_url_attributes AS node_data_field_representante_field_url_attributes, node_data_field_representante.field_telefono_value AS node_data_field_representante_field_telefono_value FROM node node LEFT JOIN content_type_cliente node_data_field_representante ON node.vid = node_data_field_representante.vid WHERE node.type in ('cliente') ORDER BY node_title ASC ) count_alias in /var/www/beissier/sites/default/modules/views/includes/view.inc on line 699.
    * user warning: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DISTINCT(node.nid), node.title AS node_title, node_data_field_representant' at line 1 query: SELECT DISTINCT(node.nid) AS DISTINCT(node.nid), node.title AS node_title, node_data_field_representante.field_representante_uid AS node_data_field_representante_field_representante_uid, node_data_field_representante.nid AS node_data_field_representante_nid, node.type AS node_type, node_data_field_representante.field_canal_venta_value AS node_data_field_representante_field_canal_venta_value, node_data_field_representante.field_email_email AS node_data_field_representante_field_email_email, node_data_field_representante.field_fax_value AS node_data_field_representante_field_fax_value, node_data_field_representante.field_persona_contacto_value AS node_data_field_representante_field_persona_contacto_value, node_data_field_representante.field_url_url AS node_data_field_representante_field_url_url, node_data_field_representante.field_url_title AS node_data_field_representante_field_url_title, node_data_field_representante.field_url_attributes AS node_data_field_representante_field_url_attributes, node_data_field_representante.field_telefono_value AS node_data_field_representante_field_telefono_value FROM node node LEFT JOIN content_type_cliente node_data_field_representante ON node.vid = node_data_field_representante.vid WHERE node.type in ('cliente') ORDER BY node_title ASC LIMIT 0, 20 in /var/www/beissier/sites/default/modules/views/includes/view.inc on line 725.