Hi @123host, thanks for your message.
Errors such as this are often picked up in Query Monitor or similar tools for our intended silent failures. We sometimes utilize WordPress’ $wpdb->suppress_errors(true); function in situations we know an error may occur. This might sound counter-intuitive but there’s no fixed amount of resources we know Wordfence will use on each customers’ server. Therefore, some non-critical situations where it’s more expensive on resources to retry or check for the presence of a file/record, we simply choose to fail silently and continue.
It looks like your case involved 2 almost simultaneous hits on the database trying to do the same thing. The first succeeded, so the second hit a duplicate entry error. Query Manager often ignores this intentional error suppression inbuilt into WordPress and presents them as issues.
Thanks,
Peter.
