Question

I want to run a mysql query to select all rows from a table films where the value of the title column does not exist anywhere in all the values of another column (collection).

Here is a simplified version of my table with content:

mysql> select * from films;
+----+--------------+--------------+
| id | title        | collection   |
+----+--------------+--------------+
|  1 | Collection 1 | NULL         |
|  2 | Film 1       | NULL         |
|  3 | Film 2       | Collection 1 |
+----+--------------+--------------+

Here is my query:

mysql> SELECT * FROM films WHERE title NOT IN (SELECT collection FROM films);
Empty set (0.00 sec)

In this example, I would want to select the rows with titles Film 1 and Film 2, but my query is returning no rows.

Here is the table structure:

CREATE TABLE `films` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `title` varchar(200) NOT NULL DEFAULT '',
  `collection` varchar(200) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM;

Answer 1

SELECT * 
FROM films 
WHERE title NOT IN (SELECT collection FROM films where collection is not null);

SQLFiddle: http://sqlfiddle.com/#!2/76278/1