如果我在 ScalarDB 中启动事务但不提交会发生什么？

Question

I am using ScalarDB to add ACID support in Cassandra application. What happens if I start a Transaction but don't commit it. Could there be any adverse effects of it?

Eg.

def somefunction=  {
    //Create the transaction
    val transaction: DistributedTransaction = transactionService.start
    if(all OK){
... //go ahead with DB operations
     commitTransaction(transaction) //OK
      (user: User, profileAndPortfolio: ExternalUserProfile, emailToken: UserToken)
    } else {
//miss commiting the transaction here
    }
  }

Answer 1

There is no effect. All mutations in a transaction are stored in the client's memory until the commit. Other transactions cannot see them and the datastore (Cassandra) doesn't receive any request for the mutations.

Answer 2

To be more correct, it might cause an anomaly (read skew anomaly or read-only transaction anomaly) if you use SERIALIZABLE with read-only transactions and use the read data.

So as a best practice, it is always better to call commit.