How to make transaction id as custom key from the header data for the event

[murali23krishna]

We have a scenario where we do not want to use the table primary key as the key, instead, I would want to use the transaction id present in the headers, is there a way to achieve it by using transformations?

[DesmondWOO]

Hi @murali23krishna ,

Thanks for reaching Qlik community.

On the transformation page, you can add a new column with $AR_H_TRANSACTION_ID value to get the transaction ID. However, 

1. There is no transaction ID for full load. It will cause skewed data to one partition.
2. A discrepancy exists between $AR_H_TRANSACTION_ID and Kafka's transactionId. For example,

$AR_H_TRANSACTION_ID : "E0FAB00100000000"
Kafka's header transactionId: "E0FAB001000000000000000000000000"

Regards,
Desmond

[murali23krishna]

Is this $AR_H_TRANSACTION_ID  is unique for every transaction or it can be duplicated across?

[DesmondWOO]

Hi @murali23krishna ,

According to the user guide , the uniqueness of the Transaction ID is not guaranteed.

Regards,
Desmond

[murali23krishna]

Is there any other field from the header can be used as unique field?

[DesmondWOO]

Hi @murali23krishna ,

Which source database are you using?

Regards,
Desmond

[murali23krishna]

It is a oracle database

[DesmondWOO]

Hi @murali23krishna ,

You can try $AR_H_CHANGE_SEQ. Please be aware that resuming the task from a previous position will result in a different change sequence for the same record.

Regards,
Desmond