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https://issues.apache.org/jira/browse/CASSANDRA-13409?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16090652#comment-16090652
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Jeff Jirsa commented on CASSANDRA-13409:
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[~slebresne] - since CASSANDRA-11475 seems to have caused this regression, and
since you probably understand current state of the engine better than anyone
else, any chance you have feedback here on the right way to solve this once and
for all?
> Materialized Views: View cells are resurrected
> ----------------------------------------------
>
> Key: CASSANDRA-13409
> URL: https://issues.apache.org/jira/browse/CASSANDRA-13409
> Project: Cassandra
> Issue Type: Bug
> Components: Local Write-Read Paths, Materialized Views
> Reporter: Duarte Nunes
> Assignee: ZhaoYang
>
> Consider the following commands, ran against trunk@0f054fee5c:
> {code:xml}
> echo "create keyspace ks WITH replication = {'class': 'SimpleStrategy',
> 'replication_factor': 1};" | bin/cqlsh
> echo "create table ks.base (p int primary key, v1 int, v2 int) with
> gc_grace_seconds = 1;" | bin/cqlsh
> echo "create materialized view ks.my_view as select * from ks.base where p is
> not null and v1 is not null primary key (v1, p);" | bin/cqlsh
> echo "insert into ks.base (p, v1, v2) values (3, 1, 3) using timestamp 1;" |
> bin/cqlsh
> bin/nodetool flush ks my_view base
> echo "delete from ks.base using timestamp 2 where p = 3;" | bin/cqlsh
> bin/nodetool flush ks my_view base
> echo "insert into ks.base (p, v1) values (3, 1) using timestamp 3;" |
> bin/cqlsh
> bin/nodetool flush ks my_view base
> echo "select * from ks.my_view;" | bin/cqlsh
> v1 | p | v2
> ----+---+----
> 1 | 3 | 3
> (1 rows)
> echo "select * from ks.base;" | bin/cqlsh
> p | v1 | v2
> ---+----+------
> 3 | 1 | null
> (1 rows)
> {code}
> As you can see, this incorrectly brings back cell v2=3.
> There is one definitive problem and a potential one:
> * Merging rows must be commutative. If a shadowable tombstone is applied
> after a row tombstone, it will replace that tombstone; if a row marker
> shadows the shadowable tombstone before the row containing the original data
> is applied, then any dead cells in said data will be resurrected;
> * Shadowable tombstones shouldn't compact away previous row tombstones or
> even deleted cells; if the relevant tombstones have been GCed from the base
> table, then a base table update won't carry them anymore (alongside a newer
> row marker).
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