I have a searchable view created that returns the following error when I click to "reset" the search query. It only occurs when resetting a search from the search terms field.
An AJAX HTTP error occurred. HTTP Result Code: 500.
The logs show the following:
PDOException: You cannot serialize or unserialize PDO instances in DrupalDatabaseCache->set() (line 455 of /code/includes/cache.inc).
This error occurs in the preview, not on the live page.