Integrity constraint violation when trying to set webform conditional

Same issue here, the following patch should solve this issue

I had this issue when exported the webform by features and tried re import it

In debugging this, I see a bigger problem. The intention of this code to is allow the conditionals to be edited, but due to the way form values are converted into the webform conditionals, the conditionals array and individual conditionals will NEVER be identical when using the conditionals-definition page.

So we can push forward and make the form values into an actual conditional (without superfluous form_state values, such as button names and weights, and with the missing nid). Or we can retreat and simply delete and re-insert the conditionals when using the conditionals page.

Worked on this a bit more. It turns out to be very hard to make the condtionals from the form exactly match the database to allow the array comparisons for delete/insert to work. There are missing fields which are supplied by the database (e.g. andor) and fields which are set during the process of the insert (the rule/action's nid/rgid/rid/aid).

I'm posting the code I used to remove the elements in the form_state that aren't in the schema, but it isn't sufficient:

/**
 * Helper. Remove non-database fields from conditionals.
 *
 * Allows edited conditionals to be compared with the conditionals in the
 * database to determine which need to be deleted and/or inserted.
 */
function webform_condiionals_form_clean($conditionals) {
  foreach (array('', 'rules', 'actions') as $suffix) {
    $raw_schema = drupal_get_schema(trim("webform_conditional_{$suffix}", '_'));
    $schema[$suffix] = $raw_schema['fields'];
  }
  foreach ($conditionals as &$conditional) {
    foreach ($conditional as $field_name => &$field_data) {
      if (isset($schema[$field_name])) {
        foreach ($field_data as &$rule_or_action) {
          foreach ($rule_or_action as $subfield_name => $subfield_data) {
            if (!isset($schema[$field_name][$subfield_name])) {
              unset($rule_or_action[$subfield_name]);
            }
          }
        }
      }
      else {
        if (!isset($schema[''][$field_name])) {
          unset($conditional[$field_name]);
        }
      }
    }
  }
  unset($conditional, $field_data, $rule_or_action); // Drop PHP references.
  return $conditionals;
}

I think the best course of action is to fix the delete/insert, understanding that for the case of editing the conditionals with the form, every conditional will be deleted and then inserted. The differential optimization code will probably work for features though.

Committed tweaked patch to 7.x-4.x. Thanks for your help everyone.

Closing to clear out the old Webform 8.x-4.x branch. See #2827845: [roadmap] YAML Form 8.x-1.x to Webform 8.x-5.x.