diff --git a/app/models/dmsf_query.rb b/app/models/dmsf_query.rb
index 0bc7b45d..ca041817 100644
--- a/app/models/dmsf_query.rb
+++ b/app/models/dmsf_query.rb
@@ -178,7 +178,7 @@ class DmsfQuery < Query
           dmsf_folders.updated_at AS updated,
           CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS major_version,
           CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS minor_version,
-          NULL AS workflow,
+          CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS workflow,
           CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS workflow_id,
           users.firstname AS firstname,
           users.lastname AS lastname,
@@ -211,7 +211,7 @@ class DmsfQuery < Query
           COALESCE(dmsf_folders.updated_at, dmsf_links.updated_at) AS updated,
           CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS major_version,
           CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS minor_version,
-          NULL AS workflow,
+          CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS workflow,
           CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS workflow_id,
           users.firstname AS firstname,
           users.lastname AS lastname,
@@ -314,7 +314,7 @@ class DmsfQuery < Query
           dmsf_links.updated_at AS updated,
 	        CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS major_version,
           CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS minor_version,
-          NULL AS workflow,
+          CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS workflow,
           CAST(NULL AS #{ActiveRecord::Base.connection.type_to_sql(:decimal)}) AS workflow_id,
           users.firstname AS firstname,
           users.lastname AS lastname,