Tim Armstrong has posted comments on this change. ( http://gerrit.cloudera.org:8080/14021 )
Change subject: IMPALA-8811 IMPALA-8813: [DOCS] Document the ACID support in Impala ...................................................................... Patch Set 5: (5 comments) http://gerrit.cloudera.org:8080/#/c/14021/5/docs/topics/impala_create_table.xml File docs/topics/impala_create_table.xml: http://gerrit.cloudera.org:8080/#/c/14021/5/docs/topics/impala_create_table.xml@388 PS5, Line 388: <p>When integrated with Hive3 and the Maybe worth calling out at the top that this only works when Impala is built with Hive 3 support? And the version of Impala that will support it? http://gerrit.cloudera.org:8080/#/c/14021/5/docs/topics/impala_transactions.xml File docs/topics/impala_transactions.xml: http://gerrit.cloudera.org:8080/#/c/14021/5/docs/topics/impala_transactions.xml@35 PS5, Line 35: satisfy ACID (Atomicity, Consistency, Isolation, Durability) properties, which intend to Impala doesn't currently support strong consistency, since Impala may operate on cached snapshots of transactional tables, and those different snapshots are not guaranteed to be in sync with each other. I think the description here is reasonably but might be misconstrued by someone as being a claim of strong consistency. It does support a weaker form of consistency. I'm not sure about the best way to describe the current guarantees that will make sense to users. Maybe Greg Rahn would have some input on this. http://gerrit.cloudera.org:8080/#/c/14021/5/docs/topics/impala_transactions.xml@41 PS5, Line 41: transactional tables at the row level. Unclear what "at the row level" means. Maybe "Specifically, Impala provides atomicity and isolation of DML operations on transactional tables. That is, the results of the DML operations are either committed in full or not committed, and the results of the DML operation are not visible to concurrent operations until the DML operation is committed." http://gerrit.cloudera.org:8080/#/c/14021/5/docs/topics/impala_transactions.xml@50 PS5, Line 50: Impala currently supports auto-committed transactions, and thus every SQL statement is an Could be clearer that this is the only behaviour, rather than an optional feature. Maybe All transactions in Impala automatically commit at the end of the statement. I.e. there are no multi-statement transactions. http://gerrit.cloudera.org:8080/#/c/14021/5/docs/topics/impala_transactions.xml@51 PS5, Line 51: automic atomic -- To view, visit http://gerrit.cloudera.org:8080/14021 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I0320e573301175dedb00d6e745f9f973519a16bb Gerrit-Change-Number: 14021 Gerrit-PatchSet: 5 Gerrit-Owner: Alex Rodoni <[email protected]> Gerrit-Reviewer: Alex Rodoni <[email protected]> Gerrit-Reviewer: Attila Jeges <[email protected]> Gerrit-Reviewer: Csaba Ringhofer <[email protected]> Gerrit-Reviewer: Greg Rahn <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Reviewer: Lars Volker <[email protected]> Gerrit-Reviewer: Tamas Mate <[email protected]> Gerrit-Reviewer: Tim Armstrong <[email protected]> Gerrit-Reviewer: Todd Lipcon <[email protected]> Gerrit-Reviewer: Zoltan Borok-Nagy <[email protected]> Gerrit-Comment-Date: Thu, 08 Aug 2019 16:06:08 +0000 Gerrit-HasComments: Yes
