[ 
https://issues.apache.org/jira/browse/CALCITE-2812?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16855028#comment-16855028
 ] 

Haisheng Yuan commented on CALCITE-2812:
----------------------------------------

SQL Server gives it name MAXRECURSION. The server-wide default is 100. When 0 
is specified, no limit is applied [1].

Should we consider aligning with one of the commercial databases?

[1] 
https://docs.microsoft.com/en-us/sql/t-sql/queries/with-common-table-expression-transact-sql?view=sql-server-2017#guidelines-for-defining-and-using-recursive-common-table-expressions

> 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: 10h
>  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. 



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Reply via email to