My SQL Subquery - Blob returned, need text value

I'm trying to write a case statement in mysql which checks if a person has booked a room. If they have, then return the roomtype, otherwise return an informative message. ``` ( CASE WHEN (eab.accommodation_id > 0) THEN (SELECT roomtype FROM event_accomodation WHERE id = eab.accommodation_id) ELSE (IFNULL(eab.accommodation_id, 'No accommodation needed')) END ) AS accommodation ``` This is the relevant part of the query. If I run it like this, BLOB is returned for every row in the accommodation column. If I change the word 'roomtype' to a column which returns an integer, it works fine. Is there a way to convert the BLOB to string within mysql? Any advice appreciated. Thanks.