diff --git a/internal/cli/client/service.go b/internal/cli/client/service.go
index dad3397c..952d6381 100644
--- a/internal/cli/client/service.go
+++ b/internal/cli/client/service.go
@@ -114,6 +114,7 @@ func (c *Client) RunService(ctx context.Context, opts *ServiceOptions) (RunServi
 			machinecore.DockerNetworkName: {},
 		},
 	}
+	// TODO: pull image if it doesn't exist on the machine.
 	createResp, err := c.CreateContainer(ctx, config, nil, netConfig, nil, containerName)
 	if err != nil {
 		return resp, fmt.Errorf("create container: %w", err)
diff --git a/internal/machine/store/schema.sql b/internal/machine/store/schema.sql
index 5366d065..e8f6463e 100644
--- a/internal/machine/store/schema.sql
+++ b/internal/machine/store/schema.sql
@@ -22,7 +22,9 @@ CREATE TABLE containers
     container    TEXT NOT NULL DEFAULT '{}' CHECK (json_valid(container)),
     machine_id   TEXT NOT NULL DEFAULT '',
     service_id   TEXT AS (json_extract(container, '$.Labels."uncloud.service.id"')),
-    service_name TEXT AS (json_extract(container, '$.Labels."uncloud.service.name"'))
+    service_name TEXT AS (json_extract(container, '$.Labels."uncloud.service.name"')),
+    -- updated_at is the last time the record was updated.
+    updated_at   TIMESTAMP NOT NULL DEFAULT '1970-01-01 00:00:00'
 );
 
 CREATE INDEX idx_machines_name ON machines (name);