Mysql根据类似计数从多个表中选择

Question

I have this problem with my sql statement and am not sure how to get around it. I am using WordPress and the WTI Like Post plugin Here is the query:

 SELECT wpblog_posts.ID, wpblog_posts.post_title, wpblog_posts.post_excerpt, wpblog_posts.guid, wpblog_posts.post_author, wpblog_wti_like_post.value, wpblog_wti_like_post.post_id 
 FROM wpblog_posts, wpblog_wti_like_post 
 LEFT JOIN wpblog_term_relationships rel ON rel.object_id = wpblog_posts.ID 
 LEFT JOIN wpblog_term_taxonomy tax ON tax.term_taxonomy_id = rel.term_taxonomy_id 
 LEFT JOIN wpblog_terms t ON t.term_id = tax.term_id WHERE t.term_id = 165 
 AND wpblog_posts.post_type = 'post' 
 AND wpblog_wti_like_post.post_id = wpblog_posts.ID 
 ORDER BY wpblog_wti_like_post.value 
 LIMIT 20 

Here is a screen shot of the wpblog_wti_like_post table:

So what i'm trying to do is select all posts from a category, and order those posts by wpblog_wti_like_post.value Now in the category some posts are liked and disliked, and appear in the table wpblog_wti_like_post but some posts don't appear in that table.

How would I:

a. Select all posts in that category

b. Order by wpblog_wti_like_post.value

I am completely stumped on how to accomplish this.

Cheers

UPDATE

This query selects all posts from a specific category and works fine, but the query above doesn't:

SELECT wpblog_posts.ID, wpblog_posts.post_title, wpblog_posts.post_excerpt, wpblog_posts.guid, wpblog_posts.post_author 
FROM wpblog_posts 
LEFT JOIN wpblog_term_relationships rel ON rel.object_id = wpblog_posts.ID 
LEFT JOIN wpblog_term_taxonomy tax ON tax.term_taxonomy_id = rel.term_taxonomy_id 
LEFT JOIN wpblog_terms t ON t.term_id = tax.term_id 
WHERE t.term_id = 165 
LIMIT 20 

Answer 1

Tip: something like the following is more readable...

SELECT p.ID
     , p.post_title
     , p.post_excerpt
     , p.guid
     , p.post_author
  FROM wpblog_posts p
  LEFT 
  JOIN wpblog_term_relationships rel 
    ON rel.object_id = p.ID
  LEFT 
  JOIN wpblog_term_taxonomy tax 
    ON tax.term_taxonomy_id = rel.term_taxonomy_id 
  LEFT 
  JOIN wpblog_terms t 
    ON t.term_id = tax.term_id
 WHERE t.term_id = 165
 LIMIT 20 

Some observations on the above:

• LEFT JOIN x... WHERE x = is the same as INNER JOIN x

• There is no point LEFT JOINing tables from which you select no columns. As stated, the above is in fact an inner join, so this fact is for future reference only.

• LIMIT without ORDER BY is fairly meaningless