Foreign key as the primary key or just separate surrogate primary key different from foreign key in JPA context
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What is the best practice to use FK as PK, or use surrogate PK, and FK just as FK in JPA context?
I saw few times people said that they had to map FK as PK, because they had legacy database. So does it mean that for new tables, if you have control to create them it is better to use the following structure:

    TABLE_1
    -------
    ID (PK)
    ...

    TABLE_2
    -------
    ID (PK) 
    TABLE_1_ID (FK)

instead of:

    TABLE_2
    -------
    TABLE_1_ID (PK) and (FK)