UPDATE wp_options SET option_value = replace(option_value, 'www.原域名.com','www.新替换域名.com') ;
UPDATE wp_posts SET post_content = replace(post_content, 'www.原域名.com','www.新替换域名.com') ;
UPDATE wp_comments SET comment_content = replace(comment_content, 'www.原域名.com', 'www.新替换域名.com') ;
UPDATE wp_comments SET comment_author_url = replace(comment_author_url, 'www.原域名.com', 'www.新替换域名.com') ;
UPDATE wp_comments
SET comment_author_email = REPLACE( comment_author_email, '原域名.com', '新替换域名.com')