@Entity
@Table(schema = "ACCOUNT", name = "RLOGTRACE", uniqueConstraints = @UniqueConstraint(columnNames = {"LOG_DT", "LOG_USER_ID", "LOG_TYPE"}))
public class RLogtrace implements java.io.Serializable {


   private RLogtraceId id;

        @EmbeddedId
        public RLogtraceId getId() {
              return this.id;
        }
............
.............
............

@Embeddable
public class RLogtraceId implements java.io.Serializable {


   private Date logDt;
   private String logUserId;
   private Character logType;

   public RLogtraceId() {
   }

   public RLogtraceId(Date logDt, String logUserId, Character logType) {
      this.logDt = logDt;
      this.logUserId = logUserId;
      this.logType = logType;
   }

   @Column(name = "LOG_DT")
        @Temporal(TemporalType.TIMESTAMP)
   public Date getLogDt() {
      return this.logDt;
   }

   public void setLogDt(Date logDt) {
      this.logDt = logDt;
   }

   @Column(name = "LOG_USER_ID", length = 30)
   public String getLogUserId() {
      return this.logUserId;
   }

   public void setLogUserId(String logUserId) {
      this.logUserId = logUserId;
   }

   @Column(name = "LOG_TYPE", length = 1)
   public Character getLogType() {
      return this.logType;
   }
..........
}

CREATE TABLE "ACCOUNT"."RLOGTRACE"
  (
    "LOG_DT" DATE,
    "LOG_USER_ID"     VARCHAR2(30 BYTE),
    "LOG_TYPE"        CHAR(1 BYTE),
.....................
.....................
  )

  TABLESPACE "ACCOUNT" ;
COMMENT ON COLUMN "ACCOUNT"."R_LOGTRACE"."LOG_DT"
IS
  'Date and time of the logged event.';
  COMMENT ON COLUMN "ACCOUNT"."R_LOGTRACE"."LOG_USER_ID"
IS
  'Related user login.';
  COMMENT ON COLUMN "ACCOUNT"."R_LOGTRACE"."LOG_TYPE"
IS
  'TYPE OF event logged:
- I FOR login event,
- O FOR logout event,

CREATE UNIQUE INDEX "ACCOUNT"."PK_R_LOGTRACE" ON "ACCOUNT"."R_LOGTRACE"
  (
    "LOG_DT", "LOG_USER_ID", "LOG_TYPE"
  )

JDBCExceptionReporter [ERROR] ORA-00001: unique constraint (ACCOUNT.PK_R_LOGTRACE) violated

2010-08-19 14:39:49 AbstractFlushingEventListener [ERROR] Could not synchronize database state with session
org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
   at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:71)

public RLogtrace updateTraceLog(Character logType, String logUserId, String logError){
      RLogtraceId rLogtraceId = new RLogtraceId();
      rLogtraceId.setLogDt(new Date());
      rLogtraceId.setLogType(logType);
      rLogtraceId.setLogUserId(logUserId);     
      RLogtrace rLogTrace = new RLogtrace();
      rLogTrace.setId(rLogtraceId);
  .....................
      rLogTrace = (RLogtrace) rLogTraceDao.create(rLogTrace);
      return rLogTrace;
   }