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Posted to commits@hive.apache.org by px...@apache.org on 2016/12/13 06:20:19 UTC
hive git commit: HIVE-13452: StatsOptimizer should return no rows on
empty table with group by (Pengcheng Xiong, reviewed by Ashutosh Chauhan)
Repository: hive
Updated Branches:
refs/heads/master 4f2fd77b7 -> cccd38422
HIVE-13452: StatsOptimizer should return no rows on empty table with group by (Pengcheng Xiong, reviewed by Ashutosh Chauhan)
Project: http://git-wip-us.apache.org/repos/asf/hive/repo
Commit: http://git-wip-us.apache.org/repos/asf/hive/commit/cccd3842
Tree: http://git-wip-us.apache.org/repos/asf/hive/tree/cccd3842
Diff: http://git-wip-us.apache.org/repos/asf/hive/diff/cccd3842
Branch: refs/heads/master
Commit: cccd38422ee8d3410d53064e282c42ad165862c7
Parents: 4f2fd77
Author: Pengcheng Xiong <px...@apache.org>
Authored: Mon Dec 12 22:20:05 2016 -0800
Committer: Pengcheng Xiong <px...@apache.org>
Committed: Mon Dec 12 22:20:05 2016 -0800
----------------------------------------------------------------------
.../hive/ql/optimizer/StatsOptimizer.java | 47 +++--
ql/src/test/queries/clientpositive/constGby.q | 21 +++
.../test/results/clientpositive/constGby.q.out | 176 +++++++++++++++++++
3 files changed, 228 insertions(+), 16 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/hive/blob/cccd3842/ql/src/java/org/apache/hadoop/hive/ql/optimizer/StatsOptimizer.java
----------------------------------------------------------------------
diff --git a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/StatsOptimizer.java b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/StatsOptimizer.java
index 17510e9..32d1de1 100644
--- a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/StatsOptimizer.java
+++ b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/StatsOptimizer.java
@@ -178,6 +178,10 @@ public class StatsOptimizer extends Transform {
abstract Object cast(double doubleValue);
}
+ enum GbyKeyType {
+ NULL, CONSTANT, OTHER
+ }
+
private StatType getType(String origType) {
if (serdeConstants.IntegralTypes.contains(origType)) {
return StatType.Integeral;
@@ -212,23 +216,23 @@ public class StatsOptimizer extends Transform {
}
}
- private boolean hasNullOrConstantGbyKey(GroupByOperator gbyOp) {
+ private GbyKeyType getGbyKeyType(GroupByOperator gbyOp) {
GroupByDesc gbyDesc = gbyOp.getConf();
int numCols = gbyDesc.getOutputColumnNames().size();
int aggCols = gbyDesc.getAggregators().size();
// If the Group by operator has null key
if (numCols == aggCols) {
- return true;
+ return GbyKeyType.NULL;
}
// If the Gby key is a constant
List<String> dpCols = gbyOp.getSchema().getColumnNames().subList(0, numCols - aggCols);
for(String dpCol : dpCols) {
ExprNodeDesc end = ExprNodeDescUtils.findConstantExprOrigin(dpCol, gbyOp);
if (!(end instanceof ExprNodeConstantDesc)) {
- return false;
+ return GbyKeyType.OTHER;
}
}
- return true;
+ return GbyKeyType.CONSTANT;
}
@Override
@@ -267,6 +271,16 @@ public class StatsOptimizer extends Transform {
// limit. In order to be safe, we do not use it now.
return null;
}
+ Table tbl = tsOp.getConf().getTableMetadata();
+ if (AcidUtils.isAcidTable(tbl)) {
+ Logger.info("Table " + tbl.getTableName() + " is ACID table. Skip StatsOptimizer.");
+ return null;
+ }
+ Long rowCnt = getRowCnt(pctx, tsOp, tbl);
+ // if we can not have correct table stats, then both the table stats and column stats are not useful.
+ if (rowCnt == null) {
+ return null;
+ }
SelectOperator pselOp = (SelectOperator)stack.get(1);
for(ExprNodeDesc desc : pselOp.getConf().getColList()) {
if (!((desc instanceof ExprNodeColumnDesc) || (desc instanceof ExprNodeConstantDesc))) {
@@ -278,7 +292,12 @@ public class StatsOptimizer extends Transform {
// Since we have done an exact match on TS-SEL-GBY-RS-GBY-(SEL)-FS
// we need not to do any instanceof checks for following.
GroupByOperator pgbyOp = (GroupByOperator)stack.get(2);
- if (!hasNullOrConstantGbyKey(pgbyOp)) {
+ if (getGbyKeyType(pgbyOp) == GbyKeyType.OTHER) {
+ return null;
+ }
+ // we already check if rowCnt is null and rowCnt==0 means table is
+ // empty.
+ else if (getGbyKeyType(pgbyOp) == GbyKeyType.CONSTANT && rowCnt == 0) {
return null;
}
ReduceSinkOperator rsOp = (ReduceSinkOperator)stack.get(3);
@@ -288,7 +307,12 @@ public class StatsOptimizer extends Transform {
}
GroupByOperator cgbyOp = (GroupByOperator)stack.get(4);
- if (!hasNullOrConstantGbyKey(cgbyOp)) {
+ if (getGbyKeyType(cgbyOp) == GbyKeyType.OTHER) {
+ return null;
+ }
+ // we already check if rowCnt is null and rowCnt==0 means table is
+ // empty.
+ else if (getGbyKeyType(cgbyOp) == GbyKeyType.CONSTANT && rowCnt == 0) {
return null;
}
Operator<?> last = (Operator<?>) stack.get(5);
@@ -318,11 +342,6 @@ public class StatsOptimizer extends Transform {
return null; // todo we can collapse this part of tree into single TS
}
- Table tbl = tsOp.getConf().getTableMetadata();
- if (AcidUtils.isAcidTable(tbl)) {
- Logger.info("Table " + tbl.getTableName() + " is ACID table. Skip StatsOptimizer.");
- return null;
- }
List<Object> oneRow = new ArrayList<Object>();
Hive hive = Hive.get(pctx.getConf());
@@ -350,10 +369,6 @@ public class StatsOptimizer extends Transform {
} else {
return null;
}
- Long rowCnt = getRowCnt(pctx, tsOp, tbl);
- if(rowCnt == null) {
- return null;
- }
switch (category) {
case LONG:
oneRow.add(Long.valueOf(constant) * rowCnt);
@@ -370,7 +385,7 @@ public class StatsOptimizer extends Transform {
}
else if (udaf instanceof GenericUDAFCount) {
// always long
- Long rowCnt = 0L;
+ rowCnt = 0L;
if (aggr.getParameters().isEmpty()) {
// Its either count (*) or count() case
rowCnt = getRowCnt(pctx, tsOp, tbl);
http://git-wip-us.apache.org/repos/asf/hive/blob/cccd3842/ql/src/test/queries/clientpositive/constGby.q
----------------------------------------------------------------------
diff --git a/ql/src/test/queries/clientpositive/constGby.q b/ql/src/test/queries/clientpositive/constGby.q
new file mode 100644
index 0000000..bde2e79
--- /dev/null
+++ b/ql/src/test/queries/clientpositive/constGby.q
@@ -0,0 +1,21 @@
+set hive.mapred.mode=nonstrict;
+
+create table t1 (a int);
+analyze table t1 compute statistics;
+analyze table t1 compute statistics for columns;
+
+explain select count(1) from t1 group by 1;
+select count(1) from t1 group by 1;
+select count(1) from t1;
+explain select count(*) from t1;
+select count(*) from t1;
+select count(1) from t1 group by 1=1;
+select count(1), max(a) from t1 group by 1=1;
+
+set hive.compute.query.using.stats=false;
+
+select count(1) from t1 group by 1;
+select count(1) from t1;
+select count(*) from t1;
+select count(1) from t1 group by 1=1;
+select count(1), max(a) from t1 group by 1=1;
http://git-wip-us.apache.org/repos/asf/hive/blob/cccd3842/ql/src/test/results/clientpositive/constGby.q.out
----------------------------------------------------------------------
diff --git a/ql/src/test/results/clientpositive/constGby.q.out b/ql/src/test/results/clientpositive/constGby.q.out
new file mode 100644
index 0000000..fd8ecc2
--- /dev/null
+++ b/ql/src/test/results/clientpositive/constGby.q.out
@@ -0,0 +1,176 @@
+PREHOOK: query: create table t1 (a int)
+PREHOOK: type: CREATETABLE
+PREHOOK: Output: database:default
+PREHOOK: Output: default@t1
+POSTHOOK: query: create table t1 (a int)
+POSTHOOK: type: CREATETABLE
+POSTHOOK: Output: database:default
+POSTHOOK: Output: default@t1
+PREHOOK: query: analyze table t1 compute statistics
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+PREHOOK: Output: default@t1
+POSTHOOK: query: analyze table t1 compute statistics
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+POSTHOOK: Output: default@t1
+PREHOOK: query: analyze table t1 compute statistics for columns
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: analyze table t1 compute statistics for columns
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+PREHOOK: query: explain select count(1) from t1 group by 1
+PREHOOK: type: QUERY
+POSTHOOK: query: explain select count(1) from t1 group by 1
+POSTHOOK: type: QUERY
+STAGE DEPENDENCIES:
+ Stage-1 is a root stage
+ Stage-0 depends on stages: Stage-1
+
+STAGE PLANS:
+ Stage: Stage-1
+ Map Reduce
+ Map Operator Tree:
+ TableScan
+ alias: t1
+ Statistics: Num rows: 1 Data size: 0 Basic stats: PARTIAL Column stats: COMPLETE
+ Select Operator
+ Statistics: Num rows: 1 Data size: 0 Basic stats: PARTIAL Column stats: COMPLETE
+ Group By Operator
+ aggregations: count(1)
+ keys: 1 (type: int)
+ mode: hash
+ outputColumnNames: _col0, _col1
+ Statistics: Num rows: 1 Data size: 8 Basic stats: COMPLETE Column stats: COMPLETE
+ Reduce Output Operator
+ key expressions: _col0 (type: int)
+ sort order: +
+ Map-reduce partition columns: _col0 (type: int)
+ Statistics: Num rows: 1 Data size: 8 Basic stats: COMPLETE Column stats: COMPLETE
+ value expressions: _col1 (type: bigint)
+ Reduce Operator Tree:
+ Group By Operator
+ aggregations: count(VALUE._col0)
+ keys: KEY._col0 (type: int)
+ mode: mergepartial
+ outputColumnNames: _col0, _col1
+ Statistics: Num rows: 1 Data size: 8 Basic stats: COMPLETE Column stats: COMPLETE
+ Select Operator
+ expressions: _col1 (type: bigint)
+ outputColumnNames: _col0
+ Statistics: Num rows: 1 Data size: 8 Basic stats: COMPLETE Column stats: COMPLETE
+ File Output Operator
+ compressed: false
+ Statistics: Num rows: 1 Data size: 8 Basic stats: COMPLETE Column stats: COMPLETE
+ table:
+ input format: org.apache.hadoop.mapred.SequenceFileInputFormat
+ output format: org.apache.hadoop.hive.ql.io.HiveSequenceFileOutputFormat
+ serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
+
+ Stage: Stage-0
+ Fetch Operator
+ limit: -1
+ Processor Tree:
+ ListSink
+
+PREHOOK: query: select count(1) from t1 group by 1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(1) from t1 group by 1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+PREHOOK: query: select count(1) from t1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(1) from t1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+0
+PREHOOK: query: explain select count(*) from t1
+PREHOOK: type: QUERY
+POSTHOOK: query: explain select count(*) from t1
+POSTHOOK: type: QUERY
+STAGE DEPENDENCIES:
+ Stage-0 is a root stage
+
+STAGE PLANS:
+ Stage: Stage-0
+ Fetch Operator
+ limit: 1
+ Processor Tree:
+ ListSink
+
+PREHOOK: query: select count(*) from t1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(*) from t1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+0
+PREHOOK: query: select count(1) from t1 group by 1=1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(1) from t1 group by 1=1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+PREHOOK: query: select count(1), max(a) from t1 group by 1=1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(1), max(a) from t1 group by 1=1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+PREHOOK: query: select count(1) from t1 group by 1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(1) from t1 group by 1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+PREHOOK: query: select count(1) from t1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(1) from t1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+0
+PREHOOK: query: select count(*) from t1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(*) from t1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+0
+PREHOOK: query: select count(1) from t1 group by 1=1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(1) from t1 group by 1=1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####
+PREHOOK: query: select count(1), max(a) from t1 group by 1=1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t1
+#### A masked pattern was here ####
+POSTHOOK: query: select count(1), max(a) from t1 group by 1=1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t1
+#### A masked pattern was here ####