diff --git a/swh/provenance/provenance.py b/swh/provenance/provenance.py
--- a/swh/provenance/provenance.py
+++ b/swh/provenance/provenance.py
@@ -251,22 +251,6 @@
                 LOGGER.warning(
                     "Unable to write directory dates to the storage. Retrying..."
                 )
-
-        revs = {
-            sha1: RevisionData(date=None, origin=None)
-            for sha1, date in self.cache["revision"]["data"].items()
-            if sha1 in self.cache["revision"]["added"] and date is not None
-        }
-        if revs:
-            while not self.storage.revision_add(revs):
-                statsd.increment(
-                    metric=BACKEND_OPERATIONS_METRIC,
-                    tags={"method": "flush_revision_content_retry_revision_none"},
-                )
-                LOGGER.warning(
-                    "Unable to write revision entities to the storage. Retrying..."
-                )
-
         paths = {
             hashlib.sha1(path).digest(): path
             for _, _, path in self.cache["content_in_revision"]
diff --git a/swh/provenance/sql/30-schema.sql b/swh/provenance/sql/30-schema.sql
--- a/swh/provenance/sql/30-schema.sql
+++ b/swh/provenance/sql/30-schema.sql
@@ -20,7 +20,7 @@
 (
     id      bigserial primary key,          -- internal identifier of the content blob
     sha1    sha1_git unique not null,       -- intrinsic identifier of the content blob
-    date    timestamptz not null            -- timestamp of the revision where the blob appears early
+    date    timestamptz                     -- timestamp of the revision where the blob appears early
 );
 comment on column content.id is 'Content internal identifier';
 comment on column content.sha1 is 'Content intrinsic identifier';
@@ -30,7 +30,7 @@
 (
     id      bigserial primary key,          -- internal identifier of the directory appearing in an isochrone inner frontier
     sha1    sha1_git unique not null,       -- intrinsic identifier of the directory
-    date    timestamptz not null,           -- max timestamp among those of the directory children's
+    date    timestamptz,                    -- max timestamp among those of the directory children's
     flat    boolean not null default false  -- flag acknowledging if the directory is flattenned in the model
 );
 comment on column directory.id is 'Directory internal identifier';
diff --git a/swh/provenance/sql/40-funcs.sql b/swh/provenance/sql/40-funcs.sql
--- a/swh/provenance/sql/40-funcs.sql
+++ b/swh/provenance/sql/40-funcs.sql
@@ -104,6 +104,27 @@
             join_location := '';
         end if;
 
+        execute format(
+            'insert into %s (sha1)
+              select src
+              from tmp_relation_add
+             on conflict do nothing',
+             src_table);
+
+        execute format(
+            'insert into %s (sha1)
+              select dst
+              from tmp_relation_add
+             on conflict do nothing',
+             dst_table);
+
+        if src_table in ('content'::regclass, 'directory'::regclass) then
+            insert into location(path)
+              select distinct path
+              from tmp_relation_add
+             on conflict do nothing;
+           end if;
+
         execute format(
             'insert into %s
                select S.id, ' || select_fields || '
@@ -283,6 +304,29 @@
         group_entries text;
         on_conflict text;
     begin
+
+        execute format(
+            'insert into %s (sha1)
+              select src
+              from tmp_relation_add
+             on conflict do nothing',
+             src_table);
+
+        execute format(
+            'insert into %s (sha1)
+              select dst
+              from tmp_relation_add
+             on conflict do nothing',
+             dst_table);
+
+        if src_table in ('content'::regclass, 'directory'::regclass) then
+            insert into location(path)
+              select distinct path
+              from tmp_relation_add
+             on conflict do nothing;
+        end if;
+
+
         if src_table in ('content'::regclass, 'directory'::regclass) then
             select_fields := 'array_agg(D.id), array_agg(L.id)';
             join_location := 'inner join location as L on (digest(L.path,''sha1'') = digest(V.path,''sha1''))';
diff --git a/swh/provenance/sql/upgrades/004.sql b/swh/provenance/sql/upgrades/004.sql
--- a/swh/provenance/sql/upgrades/004.sql
+++ b/swh/provenance/sql/upgrades/004.sql
@@ -24,3 +24,6 @@
 $$;
 
 drop type database_flavor_old;
+
+alter table content alter column date drop not null;
+alter table directory alter column date drop not null;