You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@hive.apache.org by "Nemon Lou (Jira)" <ji...@apache.org> on 2021/01/04 03:41:00 UTC
[jira] [Created] (HIVE-24579) Incorrect Result For Groupby With
Limit
Nemon Lou created HIVE-24579:
--------------------------------
Summary: Incorrect Result For Groupby With Limit
Key: HIVE-24579
URL: https://issues.apache.org/jira/browse/HIVE-24579
Project: Hive
Issue Type: Bug
Affects Versions: 3.1.2, 2.3.7, 4.0.0
Reporter: Nemon Lou
{code:sql}
create table test(id int);
explain extended select id,count(*) from test group by id limit 10;
{code}
There is an TopN unexpectly for map phase, which casues incorrect result.
{code:sql}
STAGE PLANS:
Stage: Stage-1
Map Reduce
Map Operator Tree:
TableScan
alias: test
Statistics: Num rows: 337 Data size: 1350 Basic stats: COMPLETE Column stats: NONE
GatherStats: false
Select Operator
expressions: id (type: int)
outputColumnNames: id
Statistics: Num rows: 337 Data size: 1350 Basic stats: COMPLETE Column stats: NONE
Group By Operator
aggregations: count()
keys: id (type: int)
mode: hash
outputColumnNames: _col0, _col1
Statistics: Num rows: 337 Data size: 1350 Basic stats: COMPLETE Column stats: NONE
Reduce Output Operator
key expressions: _col0 (type: int)
null sort order: a
sort order: +
Map-reduce partition columns: _col0 (type: int)
Statistics: Num rows: 337 Data size: 1350 Basic stats: COMPLETE Column stats: NONE
tag: -1
TopN: 10
TopN Hash Memory Usage: 0.1
value expressions: _col1 (type: bigint)
auto parallelism: false
Path -> Alias:
file:/user/hive/warehouse/test [test]
Path -> Partition:
file:/user/hive/warehouse/test
Partition
base file name: test
input format: org.apache.hadoop.mapred.TextInputFormat
output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat
properties:
COLUMN_STATS_ACCURATE \{"BASIC_STATS":"true"}
bucket_count -1
column.name.delimiter ,
columns id
columns.comments
columns.types int
file.inputformat org.apache.hadoop.mapred.TextInputFormat
file.outputformat org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat
location file:/user/hive/warehouse/test
name default.test
numFiles 0
numRows 0
rawDataSize 0
serialization.ddl struct test \{ i32 id}
serialization.format 1
serialization.lib org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
totalSize 0
transient_lastDdlTime 1609730036
serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
input format: org.apache.hadoop.mapred.TextInputFormat
output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat
properties:
COLUMN_STATS_ACCURATE \{"BASIC_STATS":"true"}
bucket_count -1
column.name.delimiter ,
columns id
columns.comments
columns.types int
file.inputformat org.apache.hadoop.mapred.TextInputFormat
file.outputformat org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat
location file:/user/hive/warehouse/test
name default.test
numFiles 0
numRows 0
rawDataSize 0
serialization.ddl struct test \{ i32 id}
serialization.format 1
serialization.lib org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
totalSize 0
transient_lastDdlTime 1609730036
serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
name: default.test
name: default.test
Truncated Path -> Alias:
/test [test]
Needs Tagging: false
Reduce Operator Tree:
Group By Operator
aggregations: count(VALUE._col0)
keys: KEY._col0 (type: int)
mode: mergepartial
outputColumnNames: _col0, _col1
Statistics: Num rows: 168 Data size: 672 Basic stats: COMPLETE Column stats: NONE
Limit
Number of rows: 10
Statistics: Num rows: 10 Data size: 40 Basic stats: COMPLETE Column stats: NONE
File Output Operator
compressed: false
GlobalTableId: 0
directory: file:/tmp/root/bd08973b-b58c-4185-9072-c1891f67878d/hive_2021-01-04_11-14-01_745_4475755683092435506-1/-mr-10001/.hive-staging_hive_2021-01-04_11-14-01_745_4475755683092435506-1/-ext-10002
NumFilesPerFileSink: 1
Statistics: Num rows: 10 Data size: 40 Basic stats: COMPLETE Column stats: NONE
Stats Publishing Key Prefix: file:/tmp/root/bd08973b-b58c-4185-9072-c1891f67878d/hive_2021-01-04_11-14-01_745_4475755683092435506-1/-mr-10001/.hive-staging_hive_2021-01-04_11-14-01_745_4475755683092435506-1/-ext-10002/
table:
input format: org.apache.hadoop.mapred.SequenceFileInputFormat
output format: org.apache.hadoop.hive.ql.io.HiveSequenceFileOutputFormat
properties:
columns _col0,_col1
columns.types int:bigint
escape.delim \
hive.serialization.extend.additional.nesting.levels true
serialization.escape.crlf true
serialization.format 1
serialization.lib org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
TotalFiles: 1
GatherStats: false
MultiFileSpray: false
Stage: Stage-0
Fetch Operator
limit: 10
Processor Tree:
ListSink
Time taken: 1.877 seconds, Fetched: 128 row(s)
{code}
--
This message was sent by Atlassian Jira
(v8.3.4#803005)