scalardb - 如果我只获取值，我是否需要使用提交

Question

我想检查数据库中是否存在用户。我需要使用commit吗？这段代码是获取值的正确方法吗？

val transaction: DistributedTransaction = transactionService.start
    logger.trace("transaction started: " + transaction);
    //Perform the operations you want to group in the transaction

    val pUserKey = new Key(new IntValue("bucket", utilities.bucketIDFromEmail(userKeys.bucket)),
      new TextValue("email", userKeys.email)
    )
    val cUserKey = new Key(
      new TextValue("authprovider", "credentials"),
      new TextValue("firstname", userKeys.firstName),
      new TextValue("lastname", userKeys.lastName)
    )
    logger.trace("created keys. ")
    logger.trace("getting user")
    val get:Get = new Get(pUserKey,cUserKey);

    val result:Optional[Result] = transaction.get(get);
    if(result.isPresent){
      logger.trace(s"found user ${result}")
    } else {
      logger.trace(s"user doesn't exist")
    }

    try {
      logger.trace(s"committing")
      transaction.commit()
    } catch {
      case e1:UnknownTransactionStatusException =>{
        logger.error("error in commiting. Unknowns status")
        throw e1;

      }
      case e2:CommitException =>{
        logger.error("error in commiting. Rolling back")
        transaction.abort();
        throw e2;
      }
    }

什么时候会实际获取这些值？当我打电话transaction.get或打电话时transaction.commit？

Answer 1

是的，请始终调用commitScalar DB。

默认 SNAPSHOT 实际上不需要它，但 SERIALIZABLE 需要它，因此始终调用它是一个好习惯。