jpajpa-2.1mappedby

How to use mappedBy with more than one value JPA


I have 2 tables: Currency and Rate

The currency's primary key is referenced by the inputCurrency and outputCurrency foreigh keys in the Rate.

How can I map these in order to cascadeALL?

I tried in Rate (the table that contains the foreigh keys)

@ManyToOne(cascade = CascadeType.ALL)
@JoinColumn(name = "INPUT_CURRENCY")
private Currency inputCurrency;

@ManyToOne(cascade = CascadeType.ALL)
@JoinColumn(name = "OUTPUT_CURRENCY")
private Currency ouputCurrency;

But if I delete an item from currency It results a primary key violation.I can't remove a Currency becouse it is referenced by inputCurrency or outputCurrency in Rate.

If I want to annotate the list of rates in Currency, how can I say mappedBy = "inputCurrency" and "outputCurrency" ?

@OneToMany(cascade = CascadeType.ALL,mappedBy ="inputCurrency,outputCurrency")
List<Rate> rates;

Solution

  • The solution is using two list of rates in Currency: one for the fk inputCurrency and another for the fk outputCurrency

    @OneToMany(cascade = CascadeType.ALL,mappedBy ="inputCurrency")
    List<Rate> ratesIC;
    
    @OneToMany(cascade = CascadeType.ALL,mappedBy ="outputCurrency")
    List<Rate> ratesOC;