diff --git a/database/migration/011_polygon_resolution.sql b/database/migration/011_polygon_resolution.sql
index 4b02d0b..e7e7f53 100644
--- a/database/migration/011_polygon_resolution.sql
+++ b/database/migration/011_polygon_resolution.sql
@@ -2,7 +2,7 @@
 -- 기존 데이터는 DEFAULT '6h'로 취급
 
 ALTER TABLE kcg.group_polygon_snapshots
-    ADD COLUMN IF NOT EXISTS resolution VARCHAR(4) DEFAULT '6h';
+    ADD COLUMN IF NOT EXISTS resolution VARCHAR(8) DEFAULT '6h';
 
 -- 기존 인덱스 교체: resolution 포함
 DROP INDEX IF EXISTS kcg.idx_gps_type_time;