[
https://issues.apache.org/jira/browse/CASSANDRA-12102?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Alex Petrov updated CASSANDRA-12102:
------------------------------------
Description:
{{RestrictionSet}} hierarchy was significantly improved by [CASSANDRA-11354],
although filtering-related {{Restrictions}} are split with restrictions that
would go through the 2i already in {{RowFilter}}.
There's still a clear separation, although it's currently made in {{Index}}
implementations and {{RowFilter}}, by removing things that were handled by
{{Index}} for post-filtering like it's done
[here|https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/ReadCommand.java#L374-L378].
The primary concern is that we've seen several times that there are many
corner-cases, so we may benefit from splitting columns that are handled by the
index from ones that are handled by post-filtering early in code and possibly
keeping them split for all parts of query.
I suggest to split {{ClusteringColumnRestrictions#addRowFilterTo}} into two
parts, {{addIndexRestrictions}} and {{addFilteringRestrictions}}. The change
should be quite simple and make the code simpler to understand and extend the
filtering / indexing rules.
-One problem, as noted by [~blerer] is that index decision is made on replica,
depending on cardinality, so splitting them too early might not work.- the
decision is actually made on the coordinator after [CASSANDRA-10215], although
that might involve a larger refactoring, although might still help to keep code
related to indexing / filtering together.
We can also validate that all restrictions have been respected (although we can
do that now as well).
was:
{{RestrictionSet}} hierarchy was significantly improved by [CASSANDRA-11354],
although filtering-related {{Restrictions}} are split with restrictions that
would go through the 2i already in {{RowFilter}}.
There's still a clear separation, although it's currently made in {{Index}}
implementations and {{RowFilter}}, by removing things that were handled by
{{Index}} for post-filtering like it's done
[here|https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/ReadCommand.java#L374-L378].
The primary concern is that we've seen several times that there are many
corner-cases, so we may benefit from splitting columns that are handled by the
index from ones that are handled by post-filtering early in code and possibly
keeping them split for all parts of query.
I suggest to split {{ClusteringColumnRestrictions#addRowFilterTo}} into two
parts, {{addIndexRestrictions}} and {{addFilteringRestrictions}}. The change
should be quite simple and make the code simpler to understand and extend the
filtering / indexing rules.
One problem, as noted by [~blerer] is that index decision is made on replica,
depending on cardinality, so splitting them too early might not work.
We can also validate that all restrictions have been respected (although we can
do that now as well).
> Refactor and simplify Filtering-related StatementRestriction part
> -----------------------------------------------------------------
>
> Key: CASSANDRA-12102
> URL: https://issues.apache.org/jira/browse/CASSANDRA-12102
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Alex Petrov
>
> {{RestrictionSet}} hierarchy was significantly improved by [CASSANDRA-11354],
> although filtering-related {{Restrictions}} are split with restrictions that
> would go through the 2i already in {{RowFilter}}.
> There's still a clear separation, although it's currently made in {{Index}}
> implementations and {{RowFilter}}, by removing things that were handled by
> {{Index}} for post-filtering like it's done
> [here|https://github.com/apache/cassandra/blob/trunk/src/java/org/apache/cassandra/db/ReadCommand.java#L374-L378].
>
> The primary concern is that we've seen several times that there are many
> corner-cases, so we may benefit from splitting columns that are handled by
> the index from ones that are handled by post-filtering early in code and
> possibly keeping them split for all parts of query.
> I suggest to split {{ClusteringColumnRestrictions#addRowFilterTo}} into two
> parts, {{addIndexRestrictions}} and {{addFilteringRestrictions}}. The change
> should be quite simple and make the code simpler to understand and extend the
> filtering / indexing rules.
> -One problem, as noted by [~blerer] is that index decision is made on
> replica, depending on cardinality, so splitting them too early might not
> work.- the decision is actually made on the coordinator after
> [CASSANDRA-10215], although that might involve a larger refactoring, although
> might still help to keep code related to indexing / filtering together.
> We can also validate that all restrictions have been respected (although we
> can do that now as well).
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
