I have a blog news from 1 year with around 1500 articles indexed on Google with this permalink structure (I know it is bad...):
/%category%/%postname% (without slash!)
Now I would like to change permalink structure without loosing SEO to:
/%post_id%_%postname%/ (or maybe is better this one -> /%postname%/%post_id%/)
I wrote this rule for the .htaccess but I am not sure it work well:
RewriteRule ^/([^/]+)/([^/]+)$ ^/(\d+)_([^/]+)/$ [R=301,L]
Thanks for your help!