[
https://issues.apache.org/jira/browse/CALCITE-3738?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17016606#comment-17016606
]
pengzhiwei commented on CALCITE-3738:
-------------------------------------
I think the SQL is not fully equivalent to the generated RelNode if we
remove the LogicalSort. Maybe in some usage scenario, the target table cannot
guarantee the order of the input rows. But in some case, the target table
really need the ordering of the input rows.
For example，I want to insert an ordered rows to a message queue which can
guarantee the order of the input rows. With this default optimization,I cannot
do this.
So can we make this optimization as a RelOptRule, the physics engine can
decide use or not use this rule according to the actual situation.
> Missing LogicalSort for insert statement
> ----------------------------------------
>
> Key: CALCITE-3738
> URL: https://issues.apache.org/jira/browse/CALCITE-3738
> Project: Calcite
> Issue Type: Bug
> Components: core
> Affects Versions: 1.19.0
> Reporter: pengzhiwei
> Assignee: pengzhiwei
> Priority: Major
> Labels: pull-request-available
> Time Spent: 1.5h
> Remaining Estimate: 0h
>
> The following sql statement generates a wrong logical plan which missing the
> LogicalSort :
> {code:java}
> insert into t select id*10,name from users order by name;{code}
> the plan is :
> {code:java}
> LogicalTableModify(table=[[t]], operation=[INSERT], flattened=[false])
> LogicalProject(id=[*($0, 10)], name=[$1])
> LogicalTableScan(table=[[users]])
> {code}
> This issue is introduced by the issue
> https://issues.apache.org/jira/browse/CALCITE-2978
> which removes the sort by in sub-query.However the query in insert statement
> is not a sub-query.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
