Hey,
I know whats the difference between a NULL value and an empty string ("") value, but if I want to get a value by using the OR keyword, I get no result for a NULL value

The table i want to query looks like this:

 titles_and_tags
+----+----------+------+
| id | title    | tag  |
+----+----------+------+
|  1 | title1   | NULL |
|  2 | title2   | tag1 |
|  3 | title3   | tag2 |
+----+----------+------+

The query i use looks like this:

select * from `titles_and_tags` WHERE `title` LIKE "title" AND `tag` = "tag1" OR `tag` IS NULL

So i want to get here a rows (id: 1,2), BUT this results 0 rows. What have i done wrong?