MySQL从4个表的多个联接

Question

I need to list all the poetry from users that check in for the night. I have a custom table and use wordpress.

I have a table called checkin with a field called ID which is the wordpress users id. I also have a filed called date , which is a timestamp.

The poems get stored in the ' wp0k_posts ' table, The user again is stored as ID . I need to grab of course the ' post_content ' and ' post_title ' where the ' post_type ' is equal to ' um_story '.

The real difficult part is that wordpress stores the users first name and last name in a separate table called wp0k_usermeta . user_id is equal to wp0k_users.ID . the store the values like so filed " first_name " = "Jim", " last_name " = "Harris"

I'm hoping to return: wp0k_users.ID | wp0k_usermeta.first_name | wp0k_usermeta.last_name | wp0k_posts.post_title | wp0k_posts. post_content Where checkin.date == Today

Answer 1

Looking at your question it looks like all of the table have connection to wp0k_user table . Your table naming is so confusing but here is what I've tried so far. If you could edit your question with more explanation then we could help further. :

select wu.id,wum.first_name, wum.last_name,wp.post_title,wp.post_content
from wp0k_users wu join wp0k_posts  wp on wp.user_id = wu.id
join wp0k_usermetadata wum on wum.user_id=wu.id
join checkin c on c.user_id=wu.id
where c.date >= CURDATE();