Interview Focused : Basic JPA Annotations to Remember

Basic JPA Annotations to remember
1)@Entity : Indicates to the JPA persistence provider that the class is an entity.
2)@Table :Indicates underlying database table that is represented by this entity class using the name attribute.
3)@Id : Indicates the primary key field in the class and is required for each entity.
4)@GeneratedValue : Indicates how the persistence engine should generate new primary key values for the insertion of records into the table.
5) @Basic : Indicates nullability of the field.
6) @Column : Specifies the column to which the field is mapped using the name attribute.
7) @NotNull & @Size are part of javax.validation.constraints package and define that the field cannot be null as well as the minimum and maximum sizes for the field.
8) @OneToMany : Indicates that this class may have a collection of an attribute.
9) @NamedQueries : Specifies multiple named Java Persistence query language queries. Query names are scoped to the persistence unit. The NamedQueries annotation can be applied to an entity or mapped superclass.


10) @NamedNativeQueries : Used to specify multiple native SQL named queries. Query names are scoped to the persistence unit. The NamedNativeQueries annotation can be applied to an entity or mapped superclass.

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