diff --git a/sql/archiver/swh-archiver-data.sql b/sql/archiver/swh-archiver-data.sql
index 38364e09..816a40aa 100644
--- a/sql/archiver/swh-archiver-data.sql
+++ b/sql/archiver/swh-archiver-data.sql
@@ -1,2 +1,3 @@
+INSERT INTO archive(id) VALUES('uffizi');
 INSERT INTO archive(id) VALUES('banco');
 INSERT INTO archive(id) VALUES('azure');
diff --git a/sql/archiver/swh-archiver-schema.sql b/sql/archiver/swh-archiver-schema.sql
index fffd27be..82285f01 100644
--- a/sql/archiver/swh-archiver-schema.sql
+++ b/sql/archiver/swh-archiver-schema.sql
@@ -1,59 +1,151 @@
 -- In order to archive the content of the object storage, add
 -- some tables to keep trace of what have already been archived.
 
 create table dbversion
 (
   version     int primary key,
   release     timestamptz,
   description text
 );
 
 comment on table dbversion is 'Schema update tracking';
 
 INSERT INTO dbversion(version, release, description)
-VALUES(5, now(), 'Work In Progress');
+VALUES(6, now(), 'Work In Progress');
 
 CREATE TABLE archive (
   id text PRIMARY KEY
 );
 
 comment on table archive is 'Possible archives';
 comment on column archive.id is 'Short identifier for the archive';
 
 CREATE TYPE archive_status AS ENUM (
   'missing',
   'ongoing',
   'present',
   'corrupted'
 );
 
 comment on type archive_status is 'Status of a given archive';
 
 -- a SHA1 checksum (not necessarily originating from Git)
 CREATE DOMAIN sha1 AS bytea CHECK (LENGTH(VALUE) = 20);
 
+-- a bucket for which we count items
+CREATE DOMAIN bucket AS bytea CHECK (LENGTH(VALUE) = 2);
+
 CREATE TABLE content_archive (
   content_id sha1 primary key,
   copies jsonb,
   num_present int default null
 );
 
 create index on content_archive(num_present);
 
 comment on table content_archive is 'Referencing the status and whereabouts of a content';
 comment on column content_archive.content_id is 'content identifier';
 comment on column content_archive.copies is 'map archive_id -> { "status": archive_status, "mtime": epoch timestamp }';
 comment on column content_archive.num_present is 'Number of copies marked as present (cache updated via trigger)';
 
+CREATE TABLE content_archive_counts (
+  archive text not null references archive(id),
+  bucket bucket not null,
+  count bigint,
+  primary key (archive, bucket)
+);
+
+comment on table content_archive_counts is 'Bucketed count of archive contents';
+comment on column content_archive_counts.archive is 'the archive for which we''re counting';
+comment on column content_archive_counts.bucket is 'the bucket of items we''re counting';
+comment on column content_archive_counts.count is 'the number of items counted in the given bucket';
+
 -- Keep the num_copies cache updated
 CREATE FUNCTION update_num_present() RETURNS TRIGGER AS $$
     BEGIN
     NEW.num_present := (select count(*) from jsonb_each(NEW.copies) where value->>'status' = 'present');
     RETURN new;
     END;
 $$ LANGUAGE PLPGSQL;
 
 CREATE TRIGGER update_num_present
     BEFORE INSERT OR UPDATE OF copies ON content_archive
     FOR EACH ROW
     EXECUTE PROCEDURE update_num_present();
+
+CREATE FUNCTION count_copies(from_id bytea, to_id bytea) returns void language sql as $$
+    with sample as (
+        select content_id, copies from content_archive
+        where content_id > from_id and content_id <= to_id
+    ), data as (
+        select substring(content_id from 19) as bucket, jbe.key as archive
+        from sample
+        join lateral jsonb_each(copies) jbe on true
+        where jbe.value->>'status' = 'present'
+    ), bucketed as (
+        select bucket, archive, count(*) as count
+        from data
+        group by bucket, archive
+    ) update content_archive_counts cac set
+        count = cac.count + bucketed.count
+      from bucketed
+      where cac.archive = bucketed.archive and cac.bucket = bucketed.bucket;
+$$;
+
+comment on function count_copies(bytea, bytea) is 'Count the objects between from_id and to_id, add the results to content_archive_counts';
+
+CREATE FUNCTION init_content_archive_counts() returns void language sql as $$
+    insert into content_archive_counts (
+        select id, decode(lpad(to_hex(bucket), 4, '0'), 'hex')::bucket as bucket, 0 as count
+        from archive join lateral generate_series(0, 65535) bucket on true
+    ) on conflict (archive, bucket) do nothing;
+$$;
+
+comment on function init_content_archive_counts() is 'Initialize the content archive counts for the registered archives';
+
+-- keep the content_archive_counts updated
+CREATE FUNCTION update_content_archive_counts() RETURNS TRIGGER LANGUAGE PLPGSQL AS $$
+    DECLARE
+        content_id sha1;
+        content_bucket bucket;
+        copies record;
+        old_row content_archive;
+        new_row content_archive;
+    BEGIN
+      -- default values for old or new row depending on trigger type
+      if tg_op = 'INSERT' then
+          old_row := (null::sha1, '{}'::jsonb, 0);
+      else
+          old_row := old;
+      end if;
+      if tg_op = 'DELETE' then
+          new_row := (null::sha1, '{}'::jsonb, 0);
+      else
+          new_row := new;
+      end if;
+
+      -- get the content bucket
+      content_id := coalesce(old_row.content_id, new_row.content_id);
+      content_bucket := substring(content_id from 19)::bucket;
+
+      -- compare copies present in old and new row for each archive type
+      FOR copies IN
+        select coalesce(o.key, n.key) as archive, o.value->>'status' as old_status, n.value->>'status' as new_status
+            from jsonb_each(old_row.copies) o full outer join lateral jsonb_each(new_row.copies) n on o.key = n.key
+      LOOP
+        -- the count didn't change
+        CONTINUE WHEN copies.old_status is distinct from copies.new_status OR
+                      (copies.old_status != 'present' AND copies.new_status != 'present');
+
+        update content_archive_counts cac
+            set count = count + (case when copies.old_status = 'present' then -1 else 1 end)
+            where archive = copies.archive and bucket = content_bucket;
+      END LOOP;
+      return null;
+    END;
+$$;
+
+create trigger update_content_archive_counts
+   AFTER INSERT OR UPDATE OR DELETE ON content_archive
+   FOR EACH ROW
+   EXECUTE PROCEDURE update_content_archive_counts();
diff --git a/sql/archiver/upgrades/006.sql b/sql/archiver/upgrades/006.sql
new file mode 100644
index 00000000..d9d1b24c
--- /dev/null
+++ b/sql/archiver/upgrades/006.sql
@@ -0,0 +1,100 @@
+-- SWH DB schema upgrade
+-- from_version: 5
+-- to_version: 6
+-- description: Create a bucketed count of contents in the archive.
+
+INSERT INTO dbversion(version, release, description)
+VALUES(6, now(), 'Work In Progress');
+
+-- a bucket for which we count items
+CREATE DOMAIN bucket AS bytea CHECK (LENGTH(VALUE) = 2);
+
+CREATE TABLE content_archive_counts (
+  archive text not null references archive(id),
+  bucket bucket not null,
+  count bigint,
+  primary key (archive, bucket)
+);
+
+comment on table content_archive_counts is 'Bucketed count of archive contents';
+comment on column content_archive_counts.archive is 'the archive for which we''re counting';
+comment on column content_archive_counts.bucket is 'the bucket of items we''re counting';
+comment on column content_archive_counts.count is 'the number of items counted in the given bucket';
+
+
+CREATE FUNCTION count_copies(from_id bytea, to_id bytea) returns void language sql as $$
+    with sample as (
+        select content_id, copies from content_archive
+        where content_id > from_id and content_id <= to_id
+    ), data as (
+        select substring(content_id from 19) as bucket, jbe.key as archive
+        from sample
+        join lateral jsonb_each(copies) jbe on true
+        where jbe.value->>'status' = 'present'
+    ), bucketed as (
+        select bucket, archive, count(*) as count
+        from data
+        group by bucket, archive
+    ) update content_archive_counts cac set
+        count = cac.count + bucketed.count
+      from bucketed
+      where cac.archive = bucketed.archive and cac.bucket = bucketed.bucket;
+$$;
+
+comment on function count_copies(bytea, bytea) is 'Count the objects between from_id and to_id, add the results to content_archive_counts';
+
+CREATE FUNCTION init_content_archive_counts() returns void language sql as $$
+    insert into content_archive_counts (
+        select id, decode(lpad(to_hex(bucket), 4, '0'), 'hex')::bucket as bucket, 0 as count
+        from archive join lateral generate_series(0, 65535) bucket on true
+    ) on conflict (archive, bucket) do nothing;
+$$;
+
+comment on function init_content_archive_counts() is 'Initialize the content archive counts for the registered archives';
+
+-- keep the content_archive_counts updated
+CREATE FUNCTION update_content_archive_counts() RETURNS TRIGGER LANGUAGE PLPGSQL AS $$
+    DECLARE
+        content_id sha1;
+        content_bucket bucket;
+        copies record;
+        old_row content_archive;
+        new_row content_archive;
+    BEGIN
+      -- default values for old or new row depending on trigger type
+      if tg_op = 'INSERT' then
+          old_row := (null::sha1, '{}'::jsonb, 0);
+      else
+          old_row := old;
+      end if;
+      if tg_op = 'DELETE' then
+          new_row := (null::sha1, '{}'::jsonb, 0);
+      else
+          new_row := new;
+      end if;
+
+      -- get the content bucket
+      content_id := coalesce(old_row.content_id, new_row.content_id);
+      content_bucket := substring(content_id from 19)::bucket;
+
+      -- compare copies present in old and new row for each archive type
+      FOR copies IN
+        select coalesce(o.key, n.key) as archive, o.value->>'status' as old_status, n.value->>'status' as new_status
+            from jsonb_each(old_row.copies) o full outer join lateral jsonb_each(new_row.copies) n on o.key = n.key
+      LOOP
+        -- the count didn't change
+        CONTINUE WHEN copies.old_status is distinct from copies.new_status OR
+                      (copies.old_status != 'present' AND copies.new_status != 'present');
+
+        update content_archive_counts cac
+            set count = count + (case when copies.old_status = 'present' then -1 else 1 end)
+            where archive = copies.archive and bucket = content_bucket;
+      END LOOP;
+      return null;
+    END;
+$$;
+
+create trigger update_content_archive_counts
+   AFTER INSERT OR UPDATE OR DELETE ON content_archive
+   FOR EACH ROW
+   EXECUTE PROCEDURE update_content_archive_counts();