diff --git a/sql/upgrades/161.sql b/sql/upgrades/161.sql
new file mode 100644
--- /dev/null
+++ b/sql/upgrades/161.sql
@@ -0,0 +1,17 @@
+-- SWH DB schema upgrade
+-- from_version: 160
+-- to_version: 161
+-- description: Make revision.extra_headers not null
+
+-- latest schema version
+insert into dbversion(version, release, description)
+      values(161, now(), 'Work Still In Progress');
+
+
+update revision
+    set extra_headers = ARRAY[][]
+    where extra_headers is null;
+
+
+alter table revision
+    alter column extra_headers set not null;
diff --git a/swh/storage/sql/30-swh-schema.sql b/swh/storage/sql/30-swh-schema.sql
--- a/swh/storage/sql/30-swh-schema.sql
+++ b/swh/storage/sql/30-swh-schema.sql
@@ -17,7 +17,7 @@
 
 -- latest schema version
 insert into dbversion(version, release, description)
-      values(160, now(), 'Work In Progress');
+      values(161, now(), 'Work In Progress');
 
 -- a SHA1 checksum
 create domain sha1 as bytea check (length(value) = 20);
@@ -240,7 +240,7 @@
   object_id             bigserial,
   date_neg_utc_offset   boolean,
   committer_date_neg_utc_offset boolean,
-  extra_headers         bytea[][]  -- extra headers (used in hash computation)
+  extra_headers         bytea[][] not null  -- extra headers (used in hash computation)
 );
 
 comment on table revision is 'A revision represents the state of a source code tree at a specific point in time';