diff --git a/db/migrate/20251119184052_remove_not_null_constraint_from_snippet_repositories_shard.rb b/db/migrate/20251119184052_remove_not_null_constraint_from_snippet_repositories_shard.rb
new file mode 100644
index 0000000000000000000000000000000000000000..fab1f1da76eae2b1322f6bcfd780fe70c2728c42
--- /dev/null
+++ b/db/migrate/20251119184052_remove_not_null_constraint_from_snippet_repositories_shard.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+class RemoveNotNullConstraintFromSnippetRepositoriesShard < Gitlab::Database::Migration[2.3]
+  milestone '18.7'
+
+  def up
+    change_column_null :snippet_repositories, :shard_id, true
+  end
+
+  def down
+    # No-op
+  end
+end
diff --git a/db/schema_migrations/20251119184052 b/db/schema_migrations/20251119184052
new file mode 100644
index 0000000000000000000000000000000000000000..fd293f0ed3fb88ff81a1737a88dc73680c5d5cd2
--- /dev/null
+++ b/db/schema_migrations/20251119184052
@@ -0,0 +1 @@
+6bbaa0b4a7030ac27ebeb1784ef1f95acda3b779617274bef83d081bacc5b84b
\ No newline at end of file
diff --git a/db/structure.sql b/db/structure.sql
index ed73e7ab89554002a5d59150acd3551bbc2518d5..4b241580d49747e7d73dff42a166147c4a90d12f 100644
--- a/db/structure.sql
+++ b/db/structure.sql
@@ -23075,7 +23075,7 @@ ALTER SEQUENCE personal_access_tokens_id_seq OWNED BY personal_access_tokens.id;
 
 CREATE TABLE snippet_repositories (
     snippet_id bigint NOT NULL,
-    shard_id bigint NOT NULL,
+    shard_id bigint,
     disk_path character varying(80) NOT NULL,
     verification_retry_count smallint,
     verification_retry_at timestamp with time zone,