Not supported for DML operations with JPA update query

Question

This has been asked once before but the solution did not solve the issue. I am creating a JUnit test:

 @Test
    @Transactional
    @Modifying
    public void updateMaterialInventory() throws Exception{

        // Initialize the database
        materialRepository.saveAndFlush(material);

        long id =  material.getId();
        materialRepository.updateMaterialInventory(id,UPDATED_INVENTORY_COUNT);

        assertEquals(material.getInventory_count(), UPDATED_INVENTORY_COUNT, 0);
    }

The query the above test is calling is:

 @Query("UPDATE Material m SET m.inventory_count = ?2 WHERE m.id = ?1")
    void updateMaterialInventory(Long id,int newInventoryAmount);

Error:

Caused by: org.hibernate.hql.internal.QueryExecutionRequestException: Not supported for DML operations [UPDATE com.htd.domain.Material m SET m.inventory_count = ?2 WHERE m.id = ?1]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.errorIfDML(QueryTranslatorImpl.java:318)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:369)
    at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:231)
    at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1264)
    at org.hibernate.internal.QueryImpl.list(QueryImpl.java:103)
    at org.hibernate.jpa.internal.QueryImpl.list(QueryImpl.java:573)
    at org.hibernate.jpa.internal.QueryImpl.getSingleResult(QueryImpl.java:495)
    ... 55 more

Answer 1

The @Modifying annotation must be placed on the updateMaterialInventory method, along to the @Query annotation, to let Spring-data know that the query is not a query used to select values, but to update values.

Answer 2

As far as I understand, you should not use @Transactional annotation in the repository class. Find the below answer.

Service Impl class

import org.springframework.transaction.annotation.Transactional;
...
@Test
@Transactional
public void updateMaterialInventory() throws Exception{

    // Initialize the database
    materialRepository.saveAndFlush(material);

    long id =  material.getId();
    materialRepository.updateMaterialInventory(id,UPDATED_INVENTORY_COUNT);

    assertEquals(material.getInventory_count(), UPDATED_INVENTORY_COUNT, 0);
}

Repository class

import org.springframework.data.jpa.repository.Modifying;
import org.springframework.data.jpa.repository.Query;
...

  @Modifying
  @Query("UPDATE Material m SET m.inventory_count = ?2 WHERE m.id = ?1")
  void updateMaterialInventory(Long id,int newInventoryAmount);

make sure to use the correct imports. hope this is helpful.