My smart groups show unknown counts. Debugging shows this when I click "update smart group counts".
Wordpress 5.0.3, Civi 5.9.0, PHP 7.2.14
#0 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Core/Error.php(190): CRM_Core_Error::backtrace()
#1 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/PEAR.php(921): CRM_Core_Error::handle(Object(DB_Error))
#2 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/DB.php(985): PEAR_Error->__construct("DB Error: unknown error", -1, 16, (Array:2), "CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...")
#3 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/PEAR.php(575): DB_Error->__construct(-1, 16, (Array:2), "CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...")
#4 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/PEAR.php(223): PEAR->_raiseError(Object(DB_mysqli), NULL, -1, 16, (Array:2), "CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...", "DB_Error", TRUE)
#5 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/DB/common.php(1907): PEAR->__call("raiseError", (Array:7))
#6 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/DB/mysqli.php(933): DB_common->raiseError(-1, NULL, NULL, "CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...", "1292 ** Truncated incorrect DOUBLE value: ''")
#7 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/DB/mysqli.php(403): DB_mysqli->mysqliRaiseError()
#8 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/DB/common.php(1216): DB_mysqli->simpleQuery("CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...")
#9 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/DB/DataObject.php(2415): DB_common->query("CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...")
#10 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/packages/DB/DataObject.php(1607): DB_DataObject->_query("CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...")
#11 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Core/DAO.php(438): DB_DataObject->query("CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...")
#12 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Core/DAO.php(1413): CRM_Core_DAO->query("CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...", TRUE)
#13 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/GroupContactCache.php(597): CRM_Core_DAO::executeQuery("CREATE TEMPORARY TABLE civicrm_temp_group_contact_cache384 (SELECT 14 as grou...")
#14 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/Query.php(3106): CRM_Contact_BAO_GroupContactCache::load(Object(CRM_Core_DAO))
#15 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/Query.php(3037): CRM_Contact_BAO_Query->addGroupContactCache((Array:1), NULL, "contact_a", "IN")
#16 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/Query.php(1822): CRM_Contact_BAO_Query->group((Array:5))
#17 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/Query.php(2044): CRM_Contact_BAO_Query->whereClauseSingle((Array:5), NULL)
#18 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/Query.php(531): CRM_Contact_BAO_Query->whereClause(NULL)
#19 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/Query.php(491): CRM_Contact_BAO_Query->initialize(NULL)
#20 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/Query.php(4478): CRM_Contact_BAO_Query->__construct((Array:1), (Array:1), (Array:21), TRUE, FALSE, 1, TRUE, TRUE, FALSE, NULL, "AND", NULL, "1")
#21 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/GroupContactCache.php(226): CRM_Contact_BAO_Query::apiQuery((Array:1), (Array:1), NULL, NULL, 0, 0, FALSE)
#22 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Contact/BAO/GroupContactCache.php(208): CRM_Contact_BAO_GroupContactCache::add((Array:3))
#23 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Group/Page/Group.php(129): CRM_Contact_BAO_GroupContactCache::loadAll()
#24 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Core/Page/Basic.php(160): CRM_Group_Page_Group->browse(NULL, NULL)
#25 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Core/Invoke.php(309): CRM_Core_Page_Basic->run((Array:2), NULL)
#26 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Core/Invoke.php(84): CRM_Core_Invoke::runItem((Array:13))
#27 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm/CRM/Core/Invoke.php(52): CRM_Core_Invoke::_invoke((Array:2))
#28 /var/www/sln/wordpress/wp-content/plugins/civicrm/civicrm.php(1240): CRM_Core_Invoke::invoke((Array:2))