Spring transient annotation work for save but don't work for select

Question

I am showing a grid table whit the service names with the last price register. The problem is happen when I use the @Transient in my Service class.

In this case:

I do this:

public List<Service> findAllWithPrice() {
    NativeQuery<Service> query = 
            this.getCurrentSession()
                .createSQLQuery(
                    "select s.*, FORMAT((select ps.price from priceServices ps where ps.idService = s.id order by ps.dateRegister DESC limit 1),2) as currentPrice from service s");
    query.addEntity( Service.class );

    return query.getResultList();
}

/*********************/

@Entity
@Table(name = "service")
public class Service  {
    /****/
    @Transient
    private String currentPrice;

    public String getCurrentPrice() {
        if ( currentPrice == null ) {
            return "$ 0.0";
        }
        return currentPrice;
    }
}

If I leave @Transient both save and select work but ALL prices come as zero. The currentPrice is coming null.

If I remove @Transient the select comes right. It loads the services with the last registered price for each one.

But when I save to the bank, it returns an error saying that it did not find the currentPrice column (Because it really doesn't exist).

I searched here in the forum and on the internet but I didn't find a solution.

How can I solve this problem?

Also `float` can't be `null`. Please edit the question so it's a [mcve]. — M. Prokhorov, Sep 06 '19 at 14:18
Ok, that's better. Now, the `@Transient` means that the field is [neither persisted in database nor read from it](https://stackoverflow.com/a/2154640/7470253). What you actually need is JPA's computed fields, like described here: https://stackoverflow.com/a/2986354/7470253 — M. Prokhorov, Sep 06 '19 at 14:25
Hey @M.Prokhorov, I was able to solve my problem with your tip. Thank you very much! Should I post the answer? — Donadon, Sep 06 '19 at 14:44
You should if you have one. Better to have properly a answered question, it shows up in searches better. — M. Prokhorov, Sep 06 '19 at 14:46
Thank you one more time @M.Prokhorov! I posted the answer, take a look please! — Donadon, Sep 06 '19 at 15:03

score 1 · Answer 1 · answered Sep 06 '19 at 15:02

Thanks to the @M.Prokhorov Tip, I was able to solve my problem as follows:

In my ServiceDaoImpl class, I stopped using the findAllWithPrice method to use findAll only:

public List<Service> findAll() {
    return this.getCurrentSession().createQuery("from Service", Service.class).getResultList();
}

In my Service class I created a formula to fetch the last recorded price

@Entity
@Table(name = "service")
public class Service  {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private int id;

    /****/
    @Formula("(FORMAT((select ps.price from priceServices ps where ps.idService = id order by ps.dataRegister DESC limit 1),2))")
    private String currentPrice;

    public String getCurrentPrice() {
        if ( currentPrice == null ) {
            return "$ 0.0";
        }
        return currentPrice;
    }
}

Spring transient annotation work for save but don't work for select

1 Answers1