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https://issues.apache.org/jira/browse/CALCITE-2812?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16852380#comment-16852380
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Julian Hyde commented on CALCITE-2812:
--------------------------------------
One thing I noticed: you use {{String tableName}} throughout. It would be
better to pass a {{Table}}. An enumerable table knows its own fully-qualified
name and so can generate the right code when the time comes to implement the
Enumerable.
In RelNode land, tables don't have paths or even names, and there's no notion
of "current schema", and by using tableName you're out of sync with that.
> Add algebraic operators to allow expressing recursive queries
> -------------------------------------------------------------
>
> Key: CALCITE-2812
> URL: https://issues.apache.org/jira/browse/CALCITE-2812
> Project: Calcite
> Issue Type: New Feature
> Components: core
> Affects Versions: 1.18.0
> Reporter: Stamatis Zampetakis
> Assignee: Ruben Quesada Lopez
> Priority: Major
> Labels: pull-request-available
> Fix For: 1.20.0
>
> Time Spent: 9h 40m
> Remaining Estimate: 0h
>
> In order to parse, optimize, and execute, recursive queries, expressed in
> SQL, datalog, SPARQL, or other high level language we need first to be able
> to represent recursive queries in relational algebra.
> The subject has been previously discussed in the dev list (see thread with
> title [Recursive query, graph query,
> Datalog|http://mail-archives.apache.org/mod_mbox/calcite-dev/201712.mbox/%3CCAPSgeESFyih9_hf9=uMWFN00BCR7sjf0T+FRY2=ary3ygm1...@mail.gmail.com%3E])
> where various ideas and optimizations were proposed.
> In this issue, we attempt to address only the algebraic part providing the
> following:
> # logical operator(s) for expressing recursion;
> # naive physical operator(s) for the Enumerable convention;
> # ability to create a recusive plan using the RelBuilder.
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