PostgreSQL/Oracle Table

ͨ³£ÎÒ們ÔÚ½¨Á¢ PostgreSQL/Oracle 資ÁÏ庫µÄ時ºò, Èç¹ûҪʹÓà MySQL/MS-SQL identity À×ͬµÄ¹¦ÄÜ, ¾ÍÊÇÒª採Óà Sequence 來½¨Á¢, ¶ø為ÁËÿһ個 Table ¶¼ÓÐ獨Á¢µÄÐò號產ÉúÆ÷, ÎÒ們會½¨Á¢個別µÄ sequence.
ÀýÈç (PostgreSQL sample):
CREATE SEQUENCE "student_seq" start 1 increment 1 maxvalue 2147483647 minvalue 1  cache 1;
create table student (
      id bigint PRIMARY KEY DEFAULT NEXTVAL('student_seq'),
      name character varying(50),
      studentno character varying(50)
)
當ÎÒ們ʹÓûù±¾µÄ SQL command ¾ÍÊÇ
Insert into student ( name, studentno ) values ( 'jini', '890099' )
進ÐÐ Insert µÄ動×÷, Ëû×ÔÈ»會幫ÎÒÈ¡µÃ nextval of student_seq 進ÐÐ Insert.
ÄÇ麼, ÔÚ Hibernate annotation 標準µÄ×÷·¨, ¾ÍÊÇ
@Entity
@SequenceGeneratorr(name = "TheSEQ", allocationSize = 1, initialValue = 0, sequenceName = "student_seq")
public class Student implements Serializable {
       @Id
       @GeneratedValue(strategy = GenerationType.SEQUENCE
, generator = "TheSEQ")
       private Long id;
       // other attributes, getters and setters
}
這樣, ÎÒÿһ個 @Id ¶¼µÃ»¨時間寫Ö¸¶¨µÄ sequence name,
雖È»沒ÓÐʲ麼²»ºÃ, µ«ÊÇÎÒ們¿ÉÒÔÀûÓà [tablename]_seq µÄÔ­則¶¨義 seq, ¾Í應該¿ÉÒÔ͸過 Dialect 來決¶¨ÎÒµÄ IdGenerator µÄ·½Ê½
ËùÒÔÎÒÏ£Íûδ來µÄ³Ìʽ碼Ö»ÓÐÒÔÏÂËùÁÐ, ÀûÓà AUTO ¶ø·Ç SEQUENCE generated type.
@Entity
public class Student implements Serializable {
      @Id
      @GeneratedValue(strategy=GenerationType.AUTO)
      private