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Is there any offline analytical processing? If there is, what is the difference with online analytical processing?

In What are OLTP and OLAP. What is the difference between them?, OLAP is deals with Historical Data or Archival Data. OLAP is characterized by relatively low volume of transactions. Queries are often very complex and involve aggregations.

I don't understand what does the word online in online analytical processing mean?
Is it related to real time processing(About real-time understanding: In a short time after the data is generated, this data can be analyzed. Am I wrong with this understanding)?

When does the analysis happen?
I imagine a design like this:
log generated in many apps -> kafka -> (relational DB) -> flink as ETL -> HBase, and the analysis will happen after data is inserted into HBase. Is this correct?

If yes, why is it called online?
If no, when does analysis happen? Please correct me if this design is usually not in the industry.

P.S. Assuming that the log generated by the apps in a day has a PB level

Dennis
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TLDR: as far as I can tell "Online" appears to stem from characteristics of a scenario where handling transactions with satellite devices (ATM's) was a new thing.

Long version

To understand what "online" in OLTP means, you have to go back to when ATM's first came out in the 1990s.

If you're a bank in the 1990s, you've got two types of system: your central banking system (i.e. mainframe), and these new fangled ATM's connected to it... online.

So if you're a bank, and someone wants to get money out, you have to do a balance check; and if cash is withdrawn you need to do a debit. That last action - or transaction - is key, because you don't want to miss that - you want to update your central record back in the bank's central systems. So that's the transactional processing (TP) part.

The OL part just refers to the remote / satellite / connected devices that participate in the transaction processing.

OLTP is all about making sure that happens reliably.

Adrian K
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  • Thank you for providing this point of view. I don't know the history of 1990, but I accept the definition of online for the time being. Because I am learning streaming(e.g. flink), I used to think that "online" would be related to the use or non-use of the database. – Dennis Sep 16 '21 at 16:21