#Query does not give desired result when native query is used - spring

Question

iam using spring data jpa in my project
package com.mf.acrs.model;
import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import lombok.Data;
import lombok.Getter;
import lombok.Setter;
import lombok.ToString;
#Data
#Entity(name= "mv_garage_asset_mapping")
public class GarageAssetMapping implements Serializable {
/**
*
*/
private static final long serialVersionUID = 2535545189473989744L;
#Id
#Column(name="GARAGE_CODE")
private String garageCode;
#Column(name="GARAGE_NAME")
private String garageName;
#Column(name="GARAGE_ADDRESS")
private String garageAddress;
#Column(name="GARAGE_BRANCH")
private String garageBranch;
#Column(name="CONTRACT_NUMBER")
private String contractNumber;
}
this is my entity object
package com.mf.acrs.repository;
import java.util.List;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import com.mf.acrs.model.GarageAssetMapping;
public interface GarageAssetMappingRepository extends JpaRepository<GarageAssetMapping, String> {
// #Query(name="select u.CONTRACT_NUMBER from mv_garage_asset_mapping u where u.GARAGE_CODE = ?1", nativeQuery = true) //**QUERY 1**
#Query("select u.contractNumber from mv_garage_asset_mapping u where u.garageCode = ?1") // **QUERY 2**
List<String> findByGarageCode(String garageCode);
}
this is my repository interface
when i use the QUERY 1 in my application the query fired by spring data jpa is
Hibernate: select garageasse0_.garage_code as garage_code1_2_, garageasse0_.contract_number as contract_number2_2_, garageasse0_.garage_address as garage_address3_2_, garageasse0_.garage_branch as garage_branch4_2_, garageasse0_.garage_name as garage_name5_2_ from mv_garage_asset_mapping garageasse0_ where garageasse0_.garage_code=?
but when i use QUERY 2 the query fired is
Hibernate: select garageasse0_.contract_number as col_0_0_ from mv_garage_asset_mapping garageasse0_ where garageasse0_.garage_code=?
QUERY 2 gives me desired result.
but my question is why spring data jpa fires a incorrect query in 1st case.
in QUERY 1 hibernate tries to pull all the data fields despite the fact i have explicitly written in query that i want to fetch only one field.
What mistake iam doing in this case?
The method defined in the controller which calls the method is below:
#PostMapping("/searchAssetsAjax")
#ResponseBody
public String searchAssetsAjax(#RequestBody SearchAssetData searchAssetData) throws IOException{
System.out.println("iam in the searchAssetsAjax "+searchAssetData);
System.out.println("iam in the searchAssetsAjax "+searchAssetData.toString());
// System.out.println("throwing exceptions" ); throw new IOException();
System.out.println("hitting the db "+searchAssetData.getGarageCode());
// List<String> contractNums = garageAssetMapRepository.findContractNumberByGarageCode(searchAssetData.getGarageCode());
List<String> contractNums = garageAssetMapRepository.findByGarageCode(searchAssetData.getGarageCode());
System.out.println("############contract num size is "+contractNums.size());
for(String contract: contractNums) {
System.out.println("contract nums are "+contract);
}
return "success";
}