Change permalinks in posts via SQL

If you are using MySQL 8 and above you can use REGEXP_REPLACE,

e.i.

UPDATE `wp_posts` 
SET post_content=REGEXP_REPLACE(post_content, 'domain.tld\/[0-9]{4}\/[0-9]{2}\/[0-9]{2}\/', 'domain.tld/') 
WHERE post_content REGEXP 'domain.tld\/[0-9]{4}\/[0-9]{2}\/[0-9]{2}\/';

this would look for exact match domain.tld/{4 digit int}/{2 digit int}/{2 digit int}/ then replace it with domain.tld/

so it will replace something like domain.tld/2000/01/01/my-cool-post/ to domain.tld/my-cool-post/

Another option if you cannot do it via direct SQL query;

you can query and loop through each post, then update the post_content using preg_replace

e.i

$new_post_content = preg_replace('/domain.tld\/\d{4}\/\d{2}\/\d{2}\//', 'domain.tld/', $old_post_content );

This would do the same exact match and replace as the sql query

P.S.
DO NOT forget to backup your database before doing anything, or play in a local/staging environment