Delete A Co-Author in MySQL

I too would like to know this. I mainly would like to know where I can find or how to query my database to find specific authors. I’ve looked everywhere I can think of in the DB and can’t find where coauthors are listed.

I need to change the format of dozens of usernames and when I do this, many of the posts attributed to those coauthors get disconnected somehow. I need to find the old username in my DB and replace them with the new username.

If not in the DB, is there a function that I can write up that will do this?

Any help would be appreciated. Thanks!

@gregcrowe Why not create a new admin user and delete the one in question?

@jeffsydor-bipc
Find all guest authors in posts table. *Supply your posts table name.*
Select * FROM *posts* WHERE post_type LIKE guest-author

Changing the username, 4 tables to be updated.
author = ID //is the post_id in the posts table
slug = display-name-lower-case

wp_posts
post_id| post_name
author | cap-slug

wp_post_meta
post_id| meta_key | meta_value
author | cap-user_login | slug

wp_terms (update both name and slug values)
term_id| name | slug
author | slug | cap-slug

wp_term_taxonomy
term_id| description
author | %slug% (word match in string)

Once done with edits. Clear permalink cache.
Go to Admin > Settings > Permalink and just click ‘Save Changes’.

There’s another way to do this, but it requires some programming.

You can run a script that cycles through the posts you want to reassign.
For each post, you can get the co-authors.
Then, you can filter out the undesired co-authors.
Then, you can reassign the co-authors for the post in question.

The essence:

global $coauthors_plus;
$coauthors_plus->add_coauthors(get_the_ID(), $new_coauthors);

Where $new_coauthors is an array of $u->user_nicename, with $u = get_userdata($coauthor->ID);

This is all very shorthand, but it should get you going.

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