알림삭제 기능 추가

backend/src/main/java/com/goldenchart/repository/GcTradeSignalRepository.java

@@ -2,6 +2,9 @@ package com.goldenchart.repository;
 
 import com.goldenchart.entity.GcTradeSignal;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Modifying;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 
 import java.util.List;
 
@@ -10,4 +13,13 @@ public interface GcTradeSignalRepository extends JpaRepository<GcTradeSignal, Lo
     List<GcTradeSignal> findByDeviceIdOrderByCreatedAtDesc(String deviceId);
     List<GcTradeSignal> findByUserIdOrderByCreatedAtDesc(Long userId);
     List<GcTradeSignal> findByDeviceIdAndMarketOrderByCreatedAtDesc(String deviceId, String market);
+
+    @Modifying
+    @Query("DELETE FROM GcTradeSignal e WHERE e.userId = :userId")
+    void deleteByUserId(@Param("userId") Long userId);
+
+    @Modifying
+    @Query("DELETE FROM GcTradeSignal e WHERE e.deviceId = :deviceId AND (e.userId IS NULL OR e.userId = 0)")
+    void deleteByDeviceId(@Param("deviceId") String deviceId);
+
 }