Question

I have two tables like so

subscribers

id    subscriber     subscribe_to
1       user1          user2
2       user2          user3
3       user1          user2
4       user3          user4
5       user1          user2
6       user1          user7
7       user5          user2
8       user8          user9
9       user1          user10

And my other table like so:
main

id    by_user      post_name
1     user1        somename1
2     user2        somename2
3     user1        somename3
4     user3        somename4
5     user3        somename5
6     user1        somename6
7     user2        somename7
8     user3        somename8

I want to use php-mysql to get all the subscriptions of user1 (for example) from table 1. And then pull the common name from table 2 but I am not sure how to fetch the second table

$get_subscriptions = mysql_query("SELECT * FROM `subscribers` WHERE `subscriber` = 'user1'");
if(mysql_num_rows($get_subscriptions) == 1){
$fetch = mysql_fetch_assoc($get_subscriptions);
$subscriptions = $fetch['subscribe_to'];//this will return an array with all the subscribed to users by user1
} 

Now, I want to fetch the second table and get all the post_name (from $subscriptions). I am not sure how to write the query.

$get_posts= mysql_query("SELECT * FROM `main` WHERE....");

Answer 1

Try this:

SELECT post_name FROM main 
WHERE by_user = 'user1' OR by_user IN (SELECT subscribe_to FROM subscribers WHERE subscriber = 'user1')