@@ -378,12 +378,22 @@ func (db *Database) Purge(id string) (int, error) {

 		tx.Rollback()

 		return -1, err

 	}

-

 	changes, err := rows.RowsAffected()

 	if err != nil {

 		return -1, err

 	}

+	// Clear who's using this id as parent

+	refs, err := tx.Exec("DELETE FROM edge WHERE parent_id = ?;", id)

+	if err != nil {

+		tx.Rollback()

+		return -1, err

+	}

+	refsCount, err := refs.RowsAffected()

+	if err != nil {

+		return -1, err

+	}

+

 	// Delete entity

 	if _, err := tx.Exec("DELETE FROM entity where id = ?;", id); err != nil {

 		tx.Rollback()

@@ -394,7 +404,7 @@ func (db *Database) Purge(id string) (int, error) {

 		return -1, err

 	}

-	return int(changes), nil

+	return int(changes + refsCount), nil

 }

 // Rename an edge for a given path

@@ -472,8 +472,8 @@ func TestPurgeId(t *testing.T) {

 	db.Set("/webapp", "1")

-	if db.Refs("1") != 1 {

-		t.Fatal("Expect reference count to be 1")

+	if c := db.Refs("1"); c != 1 {

+		t.Fatalf("Expect reference count to be 1, got %d", c)

 	}

 	db.Set("/db", "2")

@@ -484,7 +484,45 @@ func TestPurgeId(t *testing.T) {

 		t.Fatal(err)

 	}

 	if count != 2 {

-		t.Fatal("Expected 2 references to be removed")

+		t.Fatalf("Expected 2 references to be removed, got %d", count)

+	}

+}

+

+// Regression test https://github.com/docker/docker/issues/12334

+func TestPurgeIdRefPaths(t *testing.T) {

+	db, dbpath := newTestDb(t)

+	defer destroyTestDb(dbpath)

+

+	db.Set("/webapp", "1")

+	db.Set("/db", "2")

+

+	db.Set("/db/webapp", "1")

+

+	if c := db.Refs("1"); c != 2 {

+		t.Fatalf("Expected 2 reference for webapp, got %d", c)

+	}

+	if c := db.Refs("2"); c != 1 {

+		t.Fatalf("Expected 1 reference for db, got %d", c)

+	}

+

+	if rp := db.RefPaths("2"); len(rp) != 1 {

+		t.Fatalf("Expected 1 reference path for db, got %d", len(rp))

+	}

+

+	count, err := db.Purge("2")

+	if err != nil {

+		t.Fatal(err)

+	}

+

+	if count != 2 {

+		t.Fatalf("Expected 2 rows to be removed, got %d", count)

+	}

+

+	if c := db.Refs("2"); c != 0 {

+		t.Fatalf("Expected 0 reference for db, got %d", c)

+	}

+	if c := db.Refs("1"); c != 1 {

+		t.Fatalf("Expected 1 reference for webapp, got %d", c)

 	}

 }