Further to the problem with NRR 5.1.0.0 in my previous post, I checked the apache2 error logs and noticed that I was getting duplicate key errors for the tables referencing NRR.
WordPress database error Duplicate key name 'permalink' for query ALTER TABLE wp_now_reading ADD INDEX permalink (b_nice_author, b_nice_title) made by activate_plugin, do_action, call_user_func_array, nr_install, dbDelta, referer: https://words.mixedbredie.net/wp-admin/plugins.php?plugin_status=recent
WordPress database error Duplicate key name 'title' for query ALTER TABLE wp_now_reading ADD INDEX title (b_title) made by activate_plugin, do_action, call_user_func_array, nr_install, dbDelta, referer: https://words.mixedbredie.net/wp-admin/plugins.php?plugin_status=recent
WordPress database error Duplicate key name 'author' for query ALTER TABLE wp_now_reading ADD INDEX author (b_author) made by activate_plugin, do_action, call_user_func_array, nr_install, dbDelta, referer: https://words.mixedbredie.net/wp-admin/plugins.php?plugin_status=recent
WordPress database error Duplicate key name 'book' for query ALTER TABLE wp_now_reading_books2tags ADD INDEX book (book_id) made by activate_plugin, do_action, call_user_func_array, nr_install, dbDelta, referer: https://words.mixedbredie.net/wp-admin/plugins.php?plugin_status=recent
WordPress database error Duplicate key name 'm_key' for query ALTER TABLE wp_now_reading_meta ADD INDEX m_key (m_key) made by activate_plugin, do_action, call_user_func_array, nr_install, dbDelta, referer: https://words.mixedbredie.net/wp-admin/plugins.php?plugin_status=recent
WordPress database error Duplicate key name 't_name' for query ALTER TABLE wp_now_reading_tags ADD INDEX t_name (t_name) made by activate_plugin, do_action, call_user_func_array, nr_install, dbDelta, referer: https://words.mixedbredie.net/wp-admin/plugins.php?plugin_status=recent
Now, I don’t know if that is a problem with just my database or something that the plugin upgrade has caused but hopefully someone will be able to tell me.