diff --git a/src/utils/relation.ts b/src/utils/relation.ts
index b5ac523..fde2c6d 100644
--- a/src/utils/relation.ts
+++ b/src/utils/relation.ts
@@ -27,3 +27,7 @@ export function whereAddressQuery(query: string) {
     { subDistrict: { zipCode: { contains: query } } },
   ];
 }
+
+export function queryOrNot<T>(query: string, where: T): T | undefined {
+  return !!query ? where : undefined;
+}