diff --git a/sql/upgrades/015.sql b/sql/upgrades/015.sql
index 78db361a..97aa4f83 100644
--- a/sql/upgrades/015.sql
+++ b/sql/upgrades/015.sql
@@ -1,220 +1,222 @@
 -- SWH DB schema upgrade
 -- from_version: 14
 -- to_version: 15
 -- description: merge directory_list_* tables into directory
 
 
 insert into dbversion(version, release, description)
       values(15, now(), 'Work In Progress');
 
 alter table directory
     add column dir_entries  bigint[],
     add column file_entries bigint[],
     add column rev_entries  bigint[];
 
 with ls as (
     -- we need an explicit sub-query here, because left joins aren't allowed in
     -- update from_list
     select id,
            ls_d.entry_ids as dir_entries,
 	   ls_f.entry_ids as file_entries,
 	   ls_r.entry_ids as rev_entries
     from directory as d
     left join directory_list_dir  as ls_d on ls_d.dir_id = d.id
     left join directory_list_file as ls_f on ls_f.dir_id = d.id
     left join directory_list_rev  as ls_r on ls_r.dir_id = d.id
 )
 update directory
     set dir_entries =  ls.dir_entries,
         file_entries = ls.file_entries,
 	rev_entries =  ls.rev_entries
     from ls
     where ls.id = directory.id;
 
 create index on directory using gin (dir_entries);
 create index on directory using gin (file_entries);
 create index on directory using gin (rev_entries);
 
 drop table directory_list_dir;
 drop table directory_list_file;
 drop table directory_list_rev;
 
+drop function swh_directory_missing();
+
 create or replace function swh_directory_missing()
     returns setof sha1_git
     language plpgsql
 as $$
 begin
     return query
 	select id from tmp_directory
 	except
 	select id from directory;
     return;
 end
 $$;
 
 create or replace function swh_directory_entry_dir_add()
     returns void
     language plpgsql
 as $$
 begin
     insert into directory_entry_dir (target, name, perms, atime, mtime, ctime)
     select distinct t.target, t.name, t.perms, t.atime, t.mtime, t.ctime
     from tmp_directory_entry_dir t
     where not exists (
     select 1
     from directory_entry_dir i
     where t.target = i.target and t.name = i.name and t.perms = i.perms and
        t.atime is not distinct from i.atime and
        t.mtime is not distinct from i.mtime and
        t.ctime is not distinct from i.ctime);
 
     with new_entries as (
 	select t.dir_id, array_agg(i.id) as entries
 	from tmp_directory_entry_dir t
 	inner join directory_entry_dir i
 	on t.target = i.target and t.name = i.name and t.perms = i.perms and
 	   t.atime is not distinct from i.atime and
 	   t.mtime is not distinct from i.mtime and
 	   t.ctime is not distinct from i.ctime
 	group by t.dir_id
     )
     update directory as d
     set dir_entries = new_entries.entries
     from new_entries
     where d.id = new_entries.dir_id;
 
     return;
 end
 $$;
 
 create or replace function swh_directory_entry_file_add()
     returns void
     language plpgsql
 as $$
 begin
     insert into directory_entry_file (target, name, perms, atime, mtime, ctime)
     select distinct t.target, t.name, t.perms, t.atime, t.mtime, t.ctime
     from tmp_directory_entry_file t
     where not exists (
     select 1
     from directory_entry_file i
     where t.target = i.target and t.name = i.name and t.perms = i.perms and
        t.atime is not distinct from i.atime and
        t.mtime is not distinct from i.mtime and
        t.ctime is not distinct from i.ctime);
 
     with new_entries as (
 	select t.dir_id, array_agg(i.id) as entries
 	from tmp_directory_entry_file t
 	inner join directory_entry_file i
 	on t.target = i.target and t.name = i.name and t.perms = i.perms and
 	   t.atime is not distinct from i.atime and
 	   t.mtime is not distinct from i.mtime and
 	   t.ctime is not distinct from i.ctime
 	group by t.dir_id
     )
     update directory as d
     set file_entries = new_entries.entries
     from new_entries
     where d.id = new_entries.dir_id;
 
     return;
 end
 $$;
 
 create or replace function swh_directory_entry_rev_add()
     returns void
     language plpgsql
 as $$
 begin
     insert into directory_entry_rev (target, name, perms, atime, mtime, ctime)
     select distinct t.target, t.name, t.perms, t.atime, t.mtime, t.ctime
     from tmp_directory_entry_rev t
     where not exists (
     select 1
     from directory_entry_rev i
     where t.target = i.target and t.name = i.name and t.perms = i.perms and
        t.atime is not distinct from i.atime and
        t.mtime is not distinct from i.mtime and
        t.ctime is not distinct from i.ctime);
 
     with new_entries as (
 	select t.dir_id, array_agg(i.id) as entries
 	from tmp_directory_entry_rev t
 	inner join directory_entry_rev i
 	on t.target = i.target and t.name = i.name and t.perms = i.perms and
 	   t.atime is not distinct from i.atime and
 	   t.mtime is not distinct from i.mtime and
 	   t.ctime is not distinct from i.ctime
 	group by t.dir_id
     )
     update directory as d
     set rev_entries = new_entries.entries
     from new_entries
     where d.id = new_entries.dir_id;
 
     return;
 end
 $$;
 
 create or replace function swh_directory_walk_one(walked_dir_id sha1_git)
     returns setof directory_entry
     language plpgsql
 as $$
 begin
     return query
         with dir as (
 	    select id as dir_id, dir_entries, file_entries, rev_entries
 	    from directory
 	    where id = walked_dir_id),
 	ls_d as (select dir_id, unnest(dir_entries) as entry_id from dir),
 	ls_f as (select dir_id, unnest(file_entries) as entry_id from dir),
 	ls_r as (select dir_id, unnest(rev_entries) as entry_id from dir)
 	(select dir_id, 'dir'::directory_entry_type as type,
 	        target, name, perms, atime, mtime, ctime
 	 from ls_d
 	 left join directory_entry_dir d on ls_d.entry_id = d.id)
         union
         (select dir_id, 'file'::directory_entry_type as type,
 	        target, name, perms, atime, mtime, ctime
 	 from ls_f
 	 left join directory_entry_file d on ls_f.entry_id = d.id)
         union
         (select dir_id, 'rev'::directory_entry_type as type,
 	        target, name, perms, atime, mtime, ctime
 	 from ls_r
 	 left join directory_entry_rev d on ls_r.entry_id = d.id)
         order by name;
     return;
 end
 $$;
 
 create or replace function swh_content_find_directory(content_id sha1)
     returns content_dir
     language plpgsql
 as $$
 declare
     d content_dir;
 begin
     with recursive path as (
 	(select dir.id as dir_id, dir_entry_f.name as name, 0 as depth
 	 from directory_entry_file as dir_entry_f
 	 join content on content.sha1_git = dir_entry_f.target
 	 join directory as dir on dir.file_entries @> array[dir_entry_f.id]
 	 where content.sha1 = content_id
 	 limit 1)
 	union all
 	(select dir.id as dir_id,
 		(dir_entry_d.name || '/' || path.name)::unix_path as name,
 		path.depth + 1
 	 from path
 	 join directory_entry_dir as dir_entry_d on dir_entry_d.target = path.dir_id
 	 join directory as dir on dir.dir_entries @> array[dir_entry_d.id]
 	 limit 1)
     )
     select dir_id, name from path order by depth desc limit 1
     into strict d;
 
     return d;
 end
 $$;