Common tasks.
BEFORE ANY OF THESE
Export the affected table.
CHECKING THE SITE URL
SELECT * FROM wp_options WHERE option_name IN ('siteurl','home');
Both should be the https form of your domain.
COUNTING POST REVISIONS
SELECT COUNT(*) FROM wp_posts WHERE post_type = 'revision';
Frequently a surprisingly large number.
FINDING EXPIRED TRANSIENTS
SELECT COUNT(*) FROM wp_options WHERE option_name LIKE '%_transient_%';
These accumulate and are rarely cleared automatically.
FINDING AUTOLOADED DATA
SELECT option_name, LENGTH(option_value) FROM wp_options WHERE autoload = 'yes' ORDER BY LENGTH(option_value) DESC LIMIT 20;
Autoloaded options load on every page. A large one slows the entire site, and this query finds it.
COUNTING SPAM COMMENTS
SELECT COUNT(*) FROM wp_comments WHERE comment_approved = 'spam';
THE TABLE PREFIX
These assume wp_. Check yours in wp-config.php and adjust.
