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https://issues.apache.org/jira/browse/HIVE-17856?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16219526#comment-16219526
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Eugene Koifman commented on HIVE-17856:
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The general idea of how full Acid IOW works is given
Insert into T select * from Foo
we create a new /warehouse/db/T/base_N where N is the current txn id in which
the above SQL is running.
Then, the every acid reader uses AcidUtils.getAcidState(Path rootOfT,....) to
create a AcidUtils.Directory object which will have base_N/ files but will put
all other files in Directory.getObsolete(). This way it will only see what is
written to base_N.
All Acid readers use getAcidState() to filter the input file list wrt
ValidTxnList for each operation.
It would make sense for MM to follow the same approach. I don't think the
current MM code is quite there yet.
This would also make the Cleaner understand that deltas from before N can be
removed (but only after all the readers for them went away)
> MM tables - IOW is not ACID compliant
> -------------------------------------
>
> Key: HIVE-17856
> URL: https://issues.apache.org/jira/browse/HIVE-17856
> Project: Hive
> Issue Type: Sub-task
> Components: Transactions
> Reporter: Sergey Shelukhin
> Assignee: Steve Yeom
> Labels: mm-gap-1
>
> The following tests were removed from mm_all during "integration"... I should
> have never allowed such manner of intergration.
> MM logic should have been kept intact until ACID logic could catch up. Alas,
> here we are.
> {noformat}
> drop table iow0_mm;
> create table iow0_mm(key int) tblproperties("transactional"="true",
> "transactional_properties"="insert_only");
> insert overwrite table iow0_mm select key from intermediate;
> insert into table iow0_mm select key + 1 from intermediate;
> select * from iow0_mm order by key;
> insert overwrite table iow0_mm select key + 2 from intermediate;
> select * from iow0_mm order by key;
> drop table iow0_mm;
> drop table iow1_mm;
> create table iow1_mm(key int) partitioned by (key2 int)
> tblproperties("transactional"="true",
> "transactional_properties"="insert_only");
> insert overwrite table iow1_mm partition (key2)
> select key as k1, key from intermediate union all select key as k1, key from
> intermediate;
> insert into table iow1_mm partition (key2)
> select key + 1 as k1, key from intermediate union all select key as k1, key
> from intermediate;
> select * from iow1_mm order by key, key2;
> insert overwrite table iow1_mm partition (key2)
> select key + 3 as k1, key from intermediate union all select key + 4 as k1,
> key from intermediate;
> select * from iow1_mm order by key, key2;
> insert overwrite table iow1_mm partition (key2)
> select key + 3 as k1, key + 3 from intermediate union all select key + 2 as
> k1, key + 2 from intermediate;
> select * from iow1_mm order by key, key2;
> drop table iow1_mm;
> {noformat}
> {noformat}
> drop table simple_mm;
> create table simple_mm(key int) stored as orc tblproperties
> ("transactional"="true", "transactional_properties"="insert_only");
> insert into table simple_mm select key from intermediate;
> -insert overwrite table simple_mm select key from intermediate;
> {noformat}
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