Server CPU overload due to database error, bot?

Hi,

My site was running incredibly slowly all day, my server host said the following, below. I don’t understand what’s going on, it looks like some kind of search for a site I don’t know (www.qpyl18.com), and some Chinese characters. Here’s the message the server host support sent me:

“The VPS was using a 100% CPU, which has been investigated to be caused by the database and the FPM giving the following error:

[18-Dec-2017 16:16:55 UTC] WordPress database error Illegal mix of collations (latin1_swedish_ci,IMPLICIT) and (utf8mb4_unicode_ci,COERCIBLE) for operation ‘like’ for query SELECT SQL_CALC_FOUND_ROWS nis_posts.ID FROM nis_posts WHERE 1=1 AND (((nis_posts.post_title LIKE ‘%趣拍老虎机%’) OR (nis_posts.post_excerpt LIKE ‘%趣拍老虎机%’) OR (nis_posts.post_content LIKE ‘%趣拍老虎机%’)) AND ((nis_posts.post_title LIKE ‘%www.qpyl18.com%’) OR (nis_posts.post_excerpt LIKE ‘%www.qpyl18.com%’) OR (nis_posts.post_content LIKE ‘%www.qpyl18.com%’))) AND (nis_posts.post_password = ”) AND nis_posts.post_type IN (‘post’, ‘page’, ‘attachment’) AND (nis_posts.post_status = ‘publish’) ORDER BY (CASE WHEN nis_posts.post_title LIKE ‘%趣拍老虎机 http://www.qpyl18.com%’ THEN 1 WHEN nis_posts.post_title LIKE ‘%趣拍老虎机%’ AND nis_posts.post_title LIKE ‘%www.qpyl18.com%’ THEN 2 WHEN nis_posts.post_title LIKE ‘%趣拍老虎机%’ OR nis_posts.post_title LIKE ‘%www.qpyl18.com%’
THEN 3 WHEN nis_posts.post_excerpt LIKE ‘%趣拍老虎机 http://www.qpyl18.com%’ THEN 4 WHEN nis_posts.post_content LIKE ‘%趣拍老虎机 http://www.qpyl18.com%’ THEN 5 ELSE 6 END), nis_posts.post_date DESC LIMIT 0, 10 made by require(‘wp-blog-header.php’), wp, WP->main, WP->query_posts, WP_Query->query, WP_Query->get_posts

It seems that the collation of your database is using couple of methods which are getting into conflict and load the server and the MySQL.

Please double-check your database and advise with your developer who can further inspect the error for you. ”

The site is running fine again now, back to full speed. Is there anything I need to do?

Thanks.