Question

I have a table with a next structure:

+---------+----------+-------+
| user_id | group_id | onoff |
+---------+----------+-------+
|       1 |        3 |     1 |
+---------+----------+-------+

Here is many users and many groups. Currently max group is 18.
How can I insert group_id=19 with onoff=1 for all users in the table? (I mean insert in one query)

Answer 1

Just use a subselect clause to insert your values (MySQL docu).

INSERT INTO yourTable
  ( SELECT DISTINCT user_id, 19, 1 FROM yourTable )

Example can be seen at this sqlfiddle.