A website was blocked by webhosting because it had been compromised. It contained web shells and a lot of activity was being performed on it by crooks. wp_pcachewpr table in database with size over 2GB was one of the symptoms.
When the owner contacted me and I started to clean the site I saw a tremendeous amount of files and malware on the server. The root of the web contained several unwanted files. The original files of WordPress had been changed and malicious code added into several ones. Many sub-folders were infected with unwanted files and some very deep down in the tree.
I must admit, the crooks are clever and the pattern how the infection had been placed was well thought and planned. Some files were even placed deep down in the uploads folder which I copied over to a fresh install of WordPress. Very clever.
After the site files were cleaned I went to database to see what the wp_pcachewpr table was all about. As said, it was 2GB of size, but the contents in it were all non-readable. All numbers and symbols.
Solution to wp_pcachewpr huge table in WordPress database?
Delete it. Go to phpmyadmin, click on the table and delete it. Or have someone do it for you.
I deleted it, phpmyadmin asked for my confirmation, “am I sure I want to truncate wp_pcachewpr“. Yes, I was sure and the database size dropped to 200MB.