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https://issues.apache.org/jira/browse/PHOENIX-5148?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
chenglei updated PHOENIX-5148:
------------------------------
Description:
Given a table
{code:java}
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}
Consider following three cases:
*1. OrderBy of ClientScanPlan*
for sql:
{code:java}
select v1 from (select v1,v2,pk3 from test t where pk1 = '6' order by
t.v2,t.pk3,t.v1 limit 10) a order by v2,pk3
{code}
Obviously, the outer {{OrderBy}} "order by v2,pk3" should be compiled out
because it matchs the inner query {{OrderBy}} "order by t.v2,t.pk3,t.v1" , but
unfortunately it is not compiled out.
*2. GroupBy of ClientAggregatePlan*
for sql :
{code:java}
select v1 from (select v1,pk2,pk1 from test t where pk1 = '6' order by
t.pk2,t.v1,t.pk1 limit 10) a group by pk2,v1
{code}
Obviously, the outer {{GroupBy}} "group by pk2,v1" should be orderPreserving
because it matchs the inner query {{OrderBy}} "order by t.pk2,t.v1,t.pk1" , but
unfortunately the {{isOrderPreserving()}} of outer {{GroupBy}} return false.
*3. OrderBy of SortMergeJoinPlan(from PHOENIX-4618)*
for sql:
{code}SELECT * FROM T1 JOIN T2 ON T1.a = T2.a and T1.b = T2.b{code}
The result of the sort-merge-join is sorted on (T1.a, T1.b) and (T2.a, T2.b) at
the same time.
Thus, both 1)
{code}SELECT * FROM T1 JOIN T2 ON T1.a = T2.a and T1.b = T2.b ORDER BY T1.a,
T1.b{code}
and 2)
{code}SELECT * FROM T1 JOIN T2 ON T1.a = T2.a and T1.b = T2.b ORDER BY T2.a,
T2.b{code}
should avoid doing an extra order-by after the sort-merge-join operation.
All the above three cases are caused by the same problem that the
{{OrderPreservingTracker}} relies solely on primary keys for inferring
alignment between the target {{OrderByExpression}}s and the source sortedness.
was:
Given a table
{code:java}
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}
Consider following three cases:
*1. OrderBy of ClientScanPlan*
for sql:
{code:java}
select v1 from (select v1,v2,pk3 from test t where pk1 = '6' order by
t.v2,t.pk3,t.v1 limit 10) a order by v2,pk3
{code}
Obviously, the outer {{OrderBy}} "order by v2,pk3" should be compiled out
because it matchs the inner query {{OrderBy}} "order by t.v2,t.pk3,t.v1" , but
unfortunately it is not compiled out.
*2. GroupBy of ClientAggregatePlan*
for sql :
{code:java}
select v1 from (select v1,pk2,pk1 from test t where pk1 = '6' order by
t.pk2,t.v1,t.pk1 limit 10) a group by pk2,v1
{code}
Obviously, the outer {{GroupBy}} "group by pk2,v1" should be orderPreserving
because it matchs the inner query {{OrderBy}} "order by t.pk2,t.v1,t.pk1" , but
unfortunately the {{isOrderPreserving()}} of outer {{GroupBy}} return false.
3. SortMergeJoinPlan(from PHOENIX-4618)
> Improve OrderPreservingTracker to optimize OrderBy/GroupBy for ClientScanPlan
> and ClientAggregatePlan
> -----------------------------------------------------------------------------------------------------
>
> Key: PHOENIX-5148
> URL: https://issues.apache.org/jira/browse/PHOENIX-5148
> Project: Phoenix
> Issue Type: Improvement
> Affects Versions: 4.14.1
> Reporter: chenglei
> Priority: Major
>
> Given a table
> {code:java}
> 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}
> Consider following three cases:
> *1. OrderBy of ClientScanPlan*
> for sql:
> {code:java}
> select v1 from (select v1,v2,pk3 from test t where pk1 = '6' order by
> t.v2,t.pk3,t.v1 limit 10) a order by v2,pk3
> {code}
> Obviously, the outer {{OrderBy}} "order by v2,pk3" should be compiled out
> because it matchs the inner query {{OrderBy}} "order by t.v2,t.pk3,t.v1" ,
> but unfortunately it is not compiled out.
> *2. GroupBy of ClientAggregatePlan*
> for sql :
> {code:java}
> select v1 from (select v1,pk2,pk1 from test t where pk1 = '6' order by
> t.pk2,t.v1,t.pk1 limit 10) a group by pk2,v1
> {code}
> Obviously, the outer {{GroupBy}} "group by pk2,v1" should be orderPreserving
> because it matchs the inner query {{OrderBy}} "order by t.pk2,t.v1,t.pk1" ,
> but unfortunately the {{isOrderPreserving()}} of outer {{GroupBy}} return
> false.
> *3. OrderBy of SortMergeJoinPlan(from PHOENIX-4618)*
> for sql:
> {code}SELECT * FROM T1 JOIN T2 ON T1.a = T2.a and T1.b = T2.b{code}
> The result of the sort-merge-join is sorted on (T1.a, T1.b) and (T2.a, T2.b)
> at the same time.
> Thus, both 1)
> {code}SELECT * FROM T1 JOIN T2 ON T1.a = T2.a and T1.b = T2.b ORDER BY T1.a,
> T1.b{code}
> and 2)
> {code}SELECT * FROM T1 JOIN T2 ON T1.a = T2.a and T1.b = T2.b ORDER BY T2.a,
> T2.b{code}
> should avoid doing an extra order-by after the sort-merge-join operation.
> All the above three cases are caused by the same problem that the
> {{OrderPreservingTracker}} relies solely on primary keys for inferring
> alignment between the target {{OrderByExpression}}s and the source sortedness.
>
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