Deleting a custom field field

Is there a way to delete a custom field (in the sense of complete removal from WP database) without using a plugin?

If you have access to phpMyAdmin, these steps should do the trick:

Step 1: Login to your hosting account and launch myPHPadmin from the
cPanel, or equivalent, to access the WordPress database engine.

Step 2: Enter a select SQL command to list all the meta keys you want
to remove. In this example, I want to find and eventually remove the
meta key dcssb_short_url.

SELECT * FROM 'wp_postmeta' where 'meta_key' = 'dcssb_short_url'

Step 3: Once you are satisfied you’ve narrowed down the selection,
issue a delete SQL command to remove the rogue data

DELETE * FROM 'wp-postmeta' WHERE 'meta_key' = 'dcssb_short_url'

Step 4: Issue the same select SQL command again, to verify all the
offending records have been deleted.

SELECT * FROM 'wp_postmeta' where 'meta_key' = 'dcssb_short_url'

If you get no results returned, it means that you successfully deleted
the records.

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