我知道，这个问题已经被问过很多次了，但我的情况不同（例如，如何一次性保存父母和孩子（jpa&hibernate））
我有DTO：

@Data
public class ExchangeRatesTableDto {
    private ExchangeRatesTableType table;
    private String no;
    private LocalDate tradingDate;
    private LocalDate effectiveDate;
    private List<ExchangeRateDto> rates;
}

@Data
public class ExchangeRateDto {
    private String currency;
    private String code;
    private Double mid;
    private Double bid;
    private Double ask;
}

和实体：

@Data
@Entity
@Table(schema = DatabaseNames.SCHEMA_NBP)
public class ExchangeRatesTable {

    @Id
    @GeneratedValue(generator = "UUID")
    @GenericGenerator(name = "UUID", strategy = "org.hibernate.id.UUIDGenerator")
    private UUID id;

    @Enumerated(EnumType.ORDINAL)
    private ExchangeRatesTableType tableType;

    private String no;
    private LocalDate tradingDate;
    private LocalDate effectiveDate;

    @OneToMany(mappedBy = "exchangeRatesTable", cascade = CascadeType.ALL, orphanRemoval = true)
    private Set<ExchangeRate> exchangeRates;
}

@Data
@Entity
@Table(schema = DatabaseNames.SCHEMA_NBP)
public class ExchangeRate {

    @Id
    @GeneratedValue(generator = "UUID")
    @GenericGenerator(name = "UUID", strategy = "org.hibernate.id.UUIDGenerator")
    private UUID id;

    @ManyToOne(fetch = FetchType.LAZY, optional = false, cascade = CascadeType.ALL)
    @JoinColumn(foreignKey = @ForeignKey(name = "FK_exchange_rates_table"))
    private ExchangeRatesTable exchangeRatesTable;

    private String currency;
    private String code;
    private Double mid;
    private Double bid;
    private Double ask;
}

我也有两个存储库：

public interface ExchangeRatesTableRepository extends JpaRepository<ExchangeRatesTable, UUID> {
}

public interface ExchangeRateRepository extends JpaRepository<ExchangeRate, UUID> {
}

在控制器中，我有一个代码：

ModelMapper modelMapper = new ModelMapper();
ExchangeRatesTableDto table = exchangeRatesService.getTable(exchangeRatesTableType);
ExchangeRatesTable exchangeRatesTable = modelMapper.map(table, ExchangeRatesTable.class);
exchangeRatesTableRepository.save(exchangeRatesTable);
``` `exchangeRatesService` 退货 `ExchangeRatesTableDto` 和孩子们在一起。modelmapper返回：
![](https://i.stack.imgur.com/blP3X.png)
但是 `save` 方法无效：

Hibernate: /* insert model.ExchangeRatesTable / insert into nbp.exchange_rates_table (effective_date, no, table_type, trading_date, id) values (?, ?, ?, ?, ?)
Hibernate: / insert model.ExchangeRate */ insert into nbp.exchange_rate (ask, bid, code, currency, exchange_rates_table_id, mid, id) values (?, ?, ?, ?, ?, ?, ?)
2021-04-14 14:27:42.889 WARN 11404 --- [ main] o.h.engine.jdbc.spi.SqlExceptionHelper : SQL Error: 0, SQLState: 23502
2021-04-14 14:27:42.889 ERROR 11404 --- [ main] o.h.engine.jdbc.spi.SqlExceptionHelper : ERROR: null value in column "exchange_rates_table_id" of relation "exchange_rate" violates not-null constraint
Szczegóły: Failing row contains (f2a461e5-80ce-4837-aab9-a87919c978f8, null, null, BRL, real (Brazylia), 0.6658, null).
could not execute statement; SQL [n/a]; constraint [exchange_rates_table_id" of relation "exchange_rate]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement