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[英]Gaps In the sequence values generated by JPA @GeneratedValue with PostgreSQL
[英]How to obtain Oracle generated value from a sequence in Hibernate + JPA with @ID and @GeneratedValue
我有以下Oracle表定義。
CREATE TABLE "SIAS"."OPERATION_REG"
(
"ID" NUMBER CONSTRAINT "CT_OPERATION_REG_ID" NOT NULL ENABLE,
"OPERATION_NAME" VARCHAR2(30 BYTE),
"APPLICATION_NAME" VARCHAR2(30 BYTE),
"EXECUTION_DATE" DATE,
"EXECUTION_USER" VARCHAR2(80 BYTE),
"RESULT" VARCHAR2(20 BYTE),
CONSTRAINT "PK_OPERATION_REG_ID" PRIMARY KEY ("ID") USING INDEX PCTFREE 10
INITRANS 2 MAXTRANS 255 COMPUTE STATISTICS NOLOGGING STORAGE(INITIAL 65536 NEXT
1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST
GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
TABLESPACE "SIAS_DAT" ENABLE
)
SEGMENT CREATION IMMEDIATE PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255
NOCOMPRESS LOGGING STORAGE
(
INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE
0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT
CELL_FLASH_CACHE DEFAULT
)
TABLESPACE "SIAS_DAT" ;
CREATE UNIQUE INDEX "SIAS"."IDX_OPERATION_REG_ID" ON "SIAS"."OPERATION_REG"
(
"ID"
)
PCTFREE 10 INITRANS 2 MAXTRANS 255 COMPUTE STATISTICS NOLOGGING STORAGE
(
INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0
FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT
CELL_FLASH_CACHE DEFAULT
)
TABLESPACE "SIAS_DAT" ;
CREATE OR REPLACE TRIGGER "SIAS"."BI_OPERATION_REG" BEFORE
INSERT ON OPERATION_REG REFERENCING NEW AS NEW OLD AS OLD FOR EACH ROW BEGIN
:NEW.ID := SEQ_OPERATION_REG.NEXTVAL;
EXCEPTION
WHEN OTHERS THEN
RAISE_APPLICATION_ERROR
(
-20255, 'ERROR EN TRIGGER BI_OPERATION_REG'
)
;
END;
/
ALTER TRIGGER "SIAS"."BI_OPERATION_REG" ENABLE;
創建新行時,已啟用此觸發器以自動生成ID列的值。
create or replace
TRIGGER BI_OPERATION_REG BEFORE INSERT
ON OPERATION_REG
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
BEGIN
:NEW.ID := SEQ_OPERATION_REG.NEXTVAL;
EXCEPTION
WHEN OTHERS
THEN
RAISE_APPLICATION_ERROR (-20255, 'ERROR EN TRIGGER BI_OPERATION_REG');
END;
這是生成ID值的序列定義
CREATE SEQUENCE "SIAS"."SEQ_OPERATION_REG" MINVALUE 1 MAXVALUE
999999999999999999999999999 INCREMENT BY 1 START WITH 37 NOCACHE NOORDER NOCYCLE ;
我無法控制數據庫,因為DBA團隊不在我的權限范圍內,因此我必須處理這些定義。 我創建了一個映射OPERATION_REG表的JPA實體。 這是列ID的ID屬性方法映射。
@Id
@GeneratedValue(strategy = GenerationType.AUTO, generator = "G1")
@SequenceGenerator(name = "G1", sequenceName = "SEQ_OPERATION_REG")
@Column(name = "ID")
public int getId() {
return id;
}
這是我實體映射的完整代碼
import org.hibernate.annotations.GenericGenerator;
import javax.persistence.*;
import java.sql.Timestamp;
import java.util.Collection;
@Entity
@Table(name = "OPERATION_REG")
public class OperationRegEntity extends BaseEntity {
private int id;
private String operationName;
private String applicationName;
private Timestamp executionDate;
private String executionUser;
private String result;
private Collection<TokenRegEntity> tokenRegsById;
private Collection<TraceRegEntity> traceRegsById;
@Id
@GeneratedValue(generator="select-generator")
@GenericGenerator(name="select-generator", strategy="select", parameters = @org.hibernate.annotations.Parameter(name="key", value="ID"))
// @GeneratedValue(strategy = GenerationType.AUTO, generator = "G1")
// @SequenceGenerator(name = "G1", sequenceName = "SEQ_OPERATION_REG")
@Column(name = "ID")
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
@Basic
@Column(name = "OPERATION_NAME")
public String getOperationName() {
return operationName;
}
public void setOperationName(String operationName) {
this.operationName = operationName;
}
@Basic
@Column(name = "APPLICATION_NAME")
public String getApplicationName() {
return applicationName;
}
public void setApplicationName(String applicationName) {
this.applicationName = applicationName;
}
@Basic
@Column(name = "EXECUTION_DATE")
public Timestamp getExecutionDate() {
return executionDate;
}
public void setExecutionDate(Timestamp executionDate) {
this.executionDate = executionDate;
}
@Basic
@Column(name = "EXECUTION_USER")
public String getExecutionUser() {
return executionUser;
}
public void setExecutionUser(String executionUser) {
this.executionUser = executionUser;
}
@Basic
@Column(name = "RESULT")
public String getResult() {
return result;
}
public void setResult(String result) {
this.result = result;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
OperationRegEntity that = (OperationRegEntity) o;
if (id != that.id) return false;
if (applicationName != null ? !applicationName.equals(that.applicationName) : that.applicationName != null)
return false;
if (executionDate != null ? !executionDate.equals(that.executionDate) : that.executionDate != null)
return false;
if (executionUser != null ? !executionUser.equals(that.executionUser) : that.executionUser != null)
return false;
if (operationName != null ? !operationName.equals(that.operationName) : that.operationName != null)
return false;
if (result != null ? !result.equals(that.result) : that.result != null) return false;
return true;
}
@Override
public int hashCode() {
int result1 = id;
result1 = 31 * result1 + (operationName != null ? operationName.hashCode() : 0);
result1 = 31 * result1 + (applicationName != null ? applicationName.hashCode() : 0);
result1 = 31 * result1 + (executionDate != null ? executionDate.hashCode() : 0);
result1 = 31 * result1 + (executionUser != null ? executionUser.hashCode() : 0);
result1 = 31 * result1 + (result != null ? result.hashCode() : 0);
return result1;
}
@OneToMany(mappedBy = "operationRegByOperationRegId")
public Collection<TokenRegEntity> getTokenRegsById() {
return tokenRegsById;
}
public void setTokenRegsById(Collection<TokenRegEntity> tokenRegsById) {
this.tokenRegsById = tokenRegsById;
}
@OneToMany(mappedBy = "operationRegByOperationRegId")
public Collection<TraceRegEntity> getTraceRegsById() {
return traceRegsById;
}
public void setTraceRegsById(Collection<TraceRegEntity> traceRegsById) {
this.traceRegsById = traceRegsById;
}
}
我有一個問題,因為當我創建一個新對象並將其持久保存在數據庫中時,我會遵循這種策略
@Autowired
OperationRegService operationregservice;
@Transactional(propagation = Propagation.REQUIRES_NEW)
public OperationRegEntity createOperationReg(GenericRequestParameters parameters) {
OperationRegEntity oper = new OperationRegEntity();
oper.setApplicationName(parameters.getApplication());
oper.setExecutionUser(parameters.getApplicationUser());
oper.setOperationName(parameters.getSIASOperationName());
oper.setExecutionDate(new Timestamp(Calendar.getInstance().getTime().getTime()));
oper.setResult("INITIATED");
operationregservice.persist(oper);
return oper;
}
當我分析oper.getID()的信息時,該值與數據庫中創建的實際值不同,尤其是始終低於1點。 例如,java實體的ID值為34 ,而表行實體的ID值為35 ,就好像該序列被調用了兩次一樣。 有任何想法嗎?
您不應該使用@SequenceGenerator
,因為當您希望Hibernate在保留實體時調用序列時,可以使用@SequenceGenerator
。
在您的用例中,數據庫會進行調用,因此您需要使用select
標識符生成器策略 :
@Id
@GeneratedValue(generator="select-generator")
@GenericGenerator(name="select-generator",
strategy="select",
parameters = @org.hibernate.annotations.Parameter(name="key", value="ID")
)
@Column(name = "ID")
public int getId() {
return id;
}
好的,我找出了問題所在,並且它是觸發器生成序列的方式。 如果尚未設置ID值,關鍵是生成序列。 這樣,Hibernate將調用該序列,設置ID值,然后觸發器將檢查該值是否已設置,如果已設置,它將不調用該序列。 如果未設置任何值,則觸發器將調用序列並設置值
這是有效的觸發器
create or replace
TRIGGER BI_OPERATION_REG BEFORE INSERT
ON OPERATION_REG
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
BEGIN
IF :NEW.ID IS NULL THEN SELECT SEQ_OPERATION_REG.NEXTVAL INTO :NEW.ID FROM dual; END IF;
EXCEPTION
WHEN OTHERS
THEN
RAISE_APPLICATION_ERROR (-20255, 'ERROR EN TRIGGER BI_OPERATION_REG');
END;
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