Table1:
user_id | user_name | group_id |
1 | neo | admin |
2 | rksk | promo |
3 | nipuna | promo |
4 | face | promo |
5 | herath | help |
6 | saman | user |
7 | magneto | mod |
8 | x | user |
9 | y | user |
. | ||
. | ||
. |
post_id | title | text | user_id |
. | |||
. | |||
. |
It can do by getting "promo" group members' ids from table1 and selecting all topics made by those ids from table2.
But when those tables being larger this can be a very slower way.
Please tell me a one sql query to do that.
(I'm using PHP & Mysql)