Some times there is troubles with version of MySQL versions on your server, and its generates next error:
"WordPress database error 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 'OPTION SQL_BIG_SELECTS = 1 /* From [XXX' at line 1 for query SET OPTION SQL_BIG_SELECTS = 1 /* From [XXX] in [/site_path/
In such case do next please:
- open next file of the plugin: /views/shortcode/meta_
data_filter.php - find there code: $wpdb->query('SET OPTION SQL_BIG_SELECTS = 1') and remove OR comment this code line