JPA 2

@Table
@Column
@Enumerated
@Lob
@Temporal
@Embedable


@Enumerated


@Lob
binary large object (BLOB): char[]
character large object (CLOB): String

@Temporal(TemporalType.DATE)
protected Date creationDate;



Generating primary keys(natural keys /surrogate keys)
1. Identity columns as generators

2. Database sequences as generators

3. Sequence tables as generators

4. Default primary key generation strategy



One-to-one unidirectional relationship using @JoinColumn


One-to-one relationship using @PrimaryKeyJoinColumn


One-to-many and many-to-one


Many-to-many



Mapping Inheritance
1. Single Table
2. Joined Tables
3. Table per Class (the worst)

Single Table


Joined Table


Table per Class