coad

mysql> select t.unique_id, t.topic_name,count(distinct user_or_followers_id)as totalFollowers from topic t left join topic_followers_detail tf on tf.topic_id - t.unique_id group by 1 limit 20;
+-----------+--------------------------+----------------+
| unique_id | topic_name               | totalFollowers |
+-----------+--------------------------+----------------+
|       255 | Engineering              |             53 |
|       256 | decision making          |             58 |
|       257 | career decision          |             55 |
|       258 | rahul gandhi             |             57 |
|       259 | politician               |             58 |
|       260 | congress party           |             58 |
|       261 | surgical strike          |             58 |
|       262 | air strike               |             58 |
|       263 | strike                   |             58 |
|       264 | indian air force         |             57 |
|       265 | java                     |             57 |
|       266 | programming              |             58 |
|       267 | jsp                      |             58 |
|       268 | php                      |             58 |
|       269 | Html                     |             58 |
|       270 | ????? ???? ????? ???? ?? |             58 |
|       271 | village                  |             58 |
|       272 | city                     |             58 |
|       273 | thinking                 |             58 |
|       274 | living                   |             58 |
+-----------+--------------------------+----------------+
20 rows in set (0.41 sec)