MySQL选择具有相同ID的行（3个表）

Question

I have the following tables:

'blog_content'

'blog_media'

'blog_media_content'

| blog_id | media_id   |
========================
|  1      |      1     |         
|  2      |      2     |  
|  3      |      3     |       
|  3      |      4     |        

I want to select all blog_media.uri 's where blog_media.media_id equals blog_media_content.blog_id .

Please help me to achieve my aim.

Answer 1

An inner join between blog_media and blog_media_content tables would suffice.

SELECT 
bm.uri 
FROM blog_media bm 
INNER JOIN blog_media_content bmc ON bm.media_id = bmc.media_id
WHERE bmc.blog_id =3; 

Note:

If you need any additional information from blog table then you need an additional inner join like below:

...INNER JOIN blog_table b ON bmc.blog_id = b.blog_id...

EDIT:

In order to get records for all blog_id s :

SELECT 
bm.uri 
FROM blog_media bm 
INNER JOIN blog_media_content bmc ON bm.media_id = bmc.media_id
ORDER BY bmc.blog_id;