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chenglei updated PHOENIX-4820: ------------------------------ Attachment: (was: PHOENIX-4820_v3-4.x-HBase-1.3.patch) > Optimize OrderBy for ClientAggregatePlan > ---------------------------------------- > > Key: PHOENIX-4820 > URL: https://issues.apache.org/jira/browse/PHOENIX-4820 > Project: Phoenix > Issue Type: Improvement > Affects Versions: 4.14.0 > Reporter: chenglei > Assignee: chenglei > Priority: Major > Fix For: 4.15.0 > > Attachments: PHOENIX-4820-4.x-HBase-1.3.patch, PHOENIX-4820.diff, > PHOENIX-4820_v4-4.x-HBase-1.3.patch > > > Given a table > {code} > create table test ( > pk1 varchar not null , > pk2 varchar not null, > pk3 varchar not null, > v1 varchar, > v2 varchar, > CONSTRAINT TEST_PK PRIMARY KEY ( > pk1, > pk2, > pk3 )) > {code} > for following sql : > {code} > select a.ak3 > from (select substr(pk1,1,1) ak1,substr(pk2,1,1) ak2,substr(pk3,1,1) > ak3,substr(v1,1,1) av1,substr(v2,1,1) av2 from test order by pk2,pk3 limit > 10) a group by a.ak3,a.av1 order by a.ak3,a.av1 > {code} > Intuitively, the above OrderBy statement {{order by a.ak3,a.av1}} should be > compiled out because it match the group by statement, but in fact it is not. > The problem is caused by the {{QueryCompiler.compileSingleQuery}} and > {{QueryCompiler.compileSingleFlatQuery}},for > {{QueryCompiler.compileSingleQuery}} method,because the inner query has order > by, so in line 520, local variable {{isInRowKeyOrder}} is false: > {code} > 519 context.setCurrentTable(tableRef); > 520 boolean isInRowKeyOrder = innerPlan.getGroupBy() == > GroupBy.EMPTY_GROUP_BY && innerPlan.getOrderBy() == OrderBy.EMPTY_ORDER_BY; > {code} > In {{QueryCompiler.compileSingleFlatQuery}},when {{OrderByCompiler.compile}} > method is invoked, the last parameter {{isInRowKeyOrder}} is false: > {code} > 562 OrderBy orderBy = OrderByCompiler.compile(context, select, > groupBy, limit, offset, projector, > 563 groupBy == GroupBy.EMPTY_GROUP_BY ? > innerPlanTupleProjector : null, isInRowKeyOrder); > {code} > So in following line 156 for {{OrderByCompiler.compile}},even though the > {{tracker.isOrderPreserving}} is true, the OrderBy statement could not be > compiled out. > {code} > 156 if (isInRowKeyOrder && tracker.isOrderPreserving()) { > {code} > In my opinion, with GroupBy, in following line 563 for > {{QueryCompiler.compileSingleFlatQuery}} method, when we call > {{OrderByCompiler.compile}} method, we no need to conside the > {{isInRowKeyOrder}}, just like the previous parameter {{tupleProjector}} > does. > {code} > 562 OrderBy orderBy = OrderByCompiler.compile(context, select, > groupBy, limit, offset, projector, > 563 groupBy == GroupBy.EMPTY_GROUP_BY ? > innerPlanTupleProjector : null, isInRowKeyOrder); > {code} -- This message was sent by Atlassian JIRA (v7.6.3#76005)