@SequenceGenerator(name="GEN_PROMID",sequenceName="SEQ_PROMOTIONID",allocationSize=1)
@Id
@GeneratedValue(strategy=GenerationType.SEQUENCE,generator="GEN_PROMID")
@Column(name="PROMOTIONID")
private Long promotionid;

但即使将allocationSize指定为1,hibernate也会不一致地增加数字.以下是DB中promotionid的最新降序值

1440
1420
1407
1406
1405
1404
1403
1402
1401
1400
1380
1360
1342
1341
1340
1320
1305

我在某处读到,即使定义了@SequenceGenerator,Hibernate也可能会使用hilo seq_hilo algotihm和org.hibernate.id.SequenceHiLoGenerator生成器.另请阅读以下链接,我们可以使用@GenericGenerator来解决链接中的此问题

> http://lists.jboss.org/pipermail/hibernate-issues/2009-March/014663.html
> https://hibernate.atlassian.net/browse/ANN-354

有人可以在这种情况下抛出详细信息吗？ @GenericGenerator语法看起来不明显.应该使用@SequenceGenerator.有时@SequenceGenerator可以正常工作并生成正确的主键.

PS.我正在使用Hibernate 3.5并使用Oracle 11g DB

编辑

序列码 –

CREATE SEQUENCE SEQ_PROMOTIONID
    INCREMENT BY 1
    START WITH 100;

编辑2

更多分析表明,至少可以“总”插入一个可被20整除的值.由于Oracle的序列默认缓存为20,因此看起来正常的hibernate增量与缓存值之间存在一些冲突.还观察到当插入在它们之间有时间间隔时,它用于进入下一个可被20整除的值,否则正确地增加到1

1440    12-NOV-14 09.33.09.686000000 AM
1420    07-NOV-14 07.21.41.238000000 AM
1407    03-NOV-14 11.40.41.508000000 AM
1406    03-NOV-14 11.31.37.341000000 AM
1405    03-NOV-14 04.57.53.356000000 AM
1404    03-NOV-14 04.56.39.074000000 AM
1403    03-NOV-14 04.55.17.741000000 AM
1402    03-NOV-14 04.30.59.980000000 AM
1401    03-NOV-14 04.27.14.016000000 AM
1400    03-NOV-14 04.19.23.736000000 AM
1380    27-OCT-14 11.06.33.360000000 AM
1360    17-OCT-14 11.59.15.738000000 AM
1342    15-OCT-14 01.57.50.253000000 PM
1341    15-OCT-14 01.55.39.173000000 PM
1340    14-OCT-14 07.07.14.283000000 AM
1320    10-OCT-14 10.41.04.766000000 AM
1305    07-OCT-14 11.08.10.388000000 AM
1304    07-OCT-14 05.00.50.295000000 AM
1303    07-OCT-14 04.59.01.434000000 AM
1302    06-OCT-14 11.34.43.012000000 AM
1301    06-OCT-14 11.31.18.855000000 AM
1300    06-OCT-14 11.27.16.237000000 AM
1280    04-OCT-14 04.47.40.391000000 AM
1261    01-OCT-14 05.09.06.291000000 PM
1260    01-OCT-14 10.18.41.
@SequenceGenerator(name="GEN_PROMID",generator="GEN_PROMID")
@Column(name="PROMOTIONID")
private Long promotionid;
@SequenceGenerator(name="GEN_PROMID",generator="GEN_PROMID")
@Column(name="PROMOTIONID")
private Long promotionid;0000 AM
 1241 22-SEP-14 07.04.45.593000000 AM
 1240 22-SEP-14 04.57.25.289000000 AM
 1220 19-SEP-14 06.55.31.450000000 AM
 1200 16-SEP-14 09.03.04.763000000 AM
 1181 10-SEP-14 07.44.04.115000000 AM
 1180 08-SEP-14 11.05.30.590000000 AM
 1168 04-SEP-14 05.09.46.000000000 AM
 1167 02-SEP-14 07.47.52.454000000 AM
 1166 02-SEP-14 07.46.52.043000000 AM
 1165 02-SEP-14 07.45.38.323000000 AM
 1164 02-SEP-14 07.43.27.562000000 AM
 1163 02-SEP-14 07.41.11.702000000 AM
 1162 02-SEP-14 07.39.27.336000000 AM
 1161 02-SEP-14 07.37.35.561000000 AM
 1160 02-SEP-14 07.36.12.776000000 AM
 1140 28-AUG-14 06.09.08.346000000 AM
 1122 25-AUG-14 09.15.51.112000000 AM
 1121 25-AUG-14 09.14.30.789000000 AM
 1120 25-AUG-14 09.12.54.710000000 AM
 1100 20-AUG-14 05.46.08.394000000 AM
 1080 14-AUG-14 10.44.54.917000000 AM
 1061 09-AUG-14 06.00.43.708000000 AM
 1060 07-AUG-14 02.12.24.893000000 PM
 1042 04-AUG-14 07.34.57.224000000 AM
 1041 04-AUG-14 07.32.16.555000000 AM
 1040 04-AUG-14 07.28.34.526000000 AM
 1021 01-AUG-14 11.45.22.141000000 AM
 1020 31-JUL-14 09.46.17.765000000 AM
 1002 23-JUL-14 01.33.45.940000000 AM
 1001 22-JUL-14 11.07.54.784000000 AM
 1000 21-JUL-14 06.50.43.991000000 AM