topic Re: Header Sequence Column Question in Qlik Replicate

Header Sequence Column Question

PGN — Fri, 10 Dec 2021 16:45:57 GMT

I received this from a user, anyone have any ideas?

A question on the Attunity header sequence column

We discussed latency if it occurs over the midnight hour if a transaction was delayed for 10 min, say for one specific member with a primary key, say on the member table and the primary key is 1234567 and I have additional members on that table as 1234568 and 1234569, is it possible that Attunity would send the two records with a higher header sequence number before a record from the same table with a lower header sequence number into the CDC tables?

Re: Header Sequence Column Question

SwathiPulagam — Fri, 10 Dec 2021 17:13:49 GMT

Hi,

No, In ideal condition (Assume there are no task errors and the target is not a messaging system like Kafka)Replicate will send the records based on commit timestamp in incremental order. The time part in the header__change_seq column refers to the commit time of the transaction that includes the change record. If the transaction has members 1234568 and 1234569 committed before 1234567 then you will see a lower header sequence number for pk 1234568,1234569 and pk 1234567 will be inserted later in __ct table with a higher header sequence number.

Thanks,

Swathi

Re: Header Sequence Column Question

PGN — Fri, 10 Dec 2021 18:35:05 GMT

Great! Thanks for getting back to me so quickly.