Question

I just added users into my WordPress installation from another CMS, and now I need for each user id in wp_users insert new value with its id into wp_usermeta. Is there any ideas for this in SQL?

Answer 1

You can use a SELECT statement as a source of values for an INSERT, like this:

INSERT IGNORE INTO wp_usermeta (id)
SELECT u.id FROM wp_users u

The IGNORE keyword tells MySQL to insert the rows that it can, and if any rows we try to insert are “duplicate” rows (throw an exception), then just let those rows not be inserted, and ignore the errors that would otherwise be thrown.