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Chunwei Lei edited comment on CALCITE-2658 at 11/13/18 6:09 AM: ---------------------------------------------------------------- Thanks [~julianhyde] I will create another [jira|https://issues.apache.org/jira/browse/CALCITE-2661] to support creating Exchange and SortExchange in RelBuilder. was (Author: chunwei lei): Thanks [~julianhyde] I will create another jira to support creating Exchange and SortExchange in RelBuilder. > Introducing more ReduceExpressionRules > -------------------------------------- > > Key: CALCITE-2658 > URL: https://issues.apache.org/jira/browse/CALCITE-2658 > Project: Calcite > Issue Type: Bug > Components: core > Affects Versions: 1.17.0 > Reporter: Chunwei Lei > Assignee: Julian Hyde > Priority: Major > Fix For: 1.18.0 > > > It is useful to have rules reducing Exchange/Sort/SortExchange keys, e.g., > SELECT key,value FROM (SELECT 1 AS key, value FROM src) r DISTRIBUTE BY key; > can be reduced to > SELECT 1 AS key, value FROM src; # Since singleton requirement may already > required by SELECT. > SELECT key,value FROM (SELECT 1 AS key, value FROM src) r ORDER BY key; > can be reduced to > SELECT 1 AS key, value FROM src; # Since ordering on constant is useless. -- This message was sent by Atlassian JIRA (v7.6.3#76005)