Java代码
- @OneToMany(mappedBy = "customer",cascade = {CascadeType.ALL},fetch = FetchType.LAZY)
- private Collection<CartItem> cartItems;
- @OneToMany(mappedBy = "customer",cascade = {CascadeType.ALL},fetch = FetchType.EAGER)
- private Collection<BookOrder> orders ;
在用JPA进行注释时,如果一个实体里要映射多个集合实体时,我们不能把两个集合的的FetchType设置为EAGER,此时只能设置为LAZY,否则会报:cannot simultaneously fetch multiple bags。或者我们也可以借助:@IndexColumn
时间: 2024-10-03 04:26:44