diff --git a/app/database/001_sensors.up.sql b/app/database/001_sensors.up.sql
index f4a4203..cd8054b 100644
--- a/app/database/001_sensors.up.sql
+++ b/app/database/001_sensors.up.sql
@@ -25,7 +25,7 @@ create index idx_sensors_sensor_id on sensors (sensor_id);
 
 create table registry
 (
-    sensor_id  int       not null references sensors (id),
+    sensor_id  varchar(255)       not null references sensors (sensor_id),
 
     value      float     not null,
     created_at timestamp not null default now()