mysql> insert into searchable_content () VALUES ();
Query OK, 1 row affected (0.00 sec)

mysql> insert into searchable_content () VALUES ();
Query OK, 1 row affected (0.00 sec)

mysql> SELECT
       page_id,
       MATCH(`content`) AGAINST ('blabbity') AS 'relevance'
       FROM
       `searchable_content`  WHERE
       MATCH(`content`) AGAINST ('blabbity');
+---------+--------------------+
| page_id | relevance          |
+---------+--------------------+
|      42 | 0.3573872447013855 |
+---------+--------------------+
1 row in set (0.00 sec)

mysql> SELECT
       page_id,
       MATCH(`content`) AGAINST ('+blabbity' IN BOOLEAN MODE) AS 'relevance'
       FROM
       `searchable_content`
       WHERE MATCH(`content`) AGAINST ('+blabbity' IN BOOLEAN MODE);
+---------+-----------+
| page_id | relevance |
+---------+-----------+
|      42 |         1 |
+---------+-----------+
1 row in set (0.00 sec)