Another Repeated column in mapping for entity error
The message is clear: you have a repeated column in the mapping. That means you mapped the same database column twice. And indeed, you have: @Column(nullable=false) private Long customerId; and also: @ManyToOne(optional=false) @JoinColumn(name=”customerId”,referencedColumnName=”id_customer”) private Customer customer; (and the same goes for productId/product). You shouldn’t reference other entities by their ID, but by a direct reference … Read more