diff --git a/sql/upgrades/118.sql b/sql/upgrades/118.sql
index b2c4930..e842566 100644
--- a/sql/upgrades/118.sql
+++ b/sql/upgrades/118.sql
@@ -1,11 +1,13 @@
 -- SWH Indexer DB schema upgrade
 -- from_version: 117
 -- to_version: 118
 -- description: content_mimetype: Migrate bytes column to text
 
 insert into dbversion(version, release, description)
 values(118, now(), 'Work In Progress');
 
 alter table content_mimetype
-  alter column mimetype set data type text,
-  alter column encoding set data type text;
+  alter column mimetype set data type text
+    using convert_from(mimetype, 'utf-8'),
+  alter column encoding set data type text
+    using convert_from(encoding, 'utf-8');