Dandandan opened a new issue #917:
URL: https://github.com/apache/arrow-datafusion/issues/917
**Describe the bug**
A simple query like `select max(l_partkey) from lineitem` has a different
plan when using `explain analyze` than what is executed when trying a normal
`select`.
The output from `explain analyze` is slower than normal and hasn't the
statistics-based optimization enabled:
```
+-------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| plan_type | plan
|
+-------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Plan with Metrics | ProjectionExec: expr=[MAX(lineitem.l_partkey)@0 as
MAX(l_partkey)], metrics=[]
|
| | HashAggregateExec: mode=Final, gby=[],
aggr=[MAX(l_partkey)], metrics=[outputRows=0]
|
| | CoalescePartitionsExec, metrics=[]
|
| | HashAggregateExec: mode=Partial, gby=[],
aggr=[MAX(l_partkey)], metrics=[outputRows=0]
|
| | RepartitionExec:
partitioning=RoundRobinBatch(16), metrics=[fetchTime=51231297,
repartitionTime=0, sendTime=120310]
|
| | ParquetExec: batch_size=8192, limit=None,
partitions=[../benchmarks/parquet/lineitem/part-0.parquet],
metrics=[numPredicateCreationErrors=0, numPredicateEvaluationErrors for
../benchmarks/parquet/lineitem/part-0.parquet=0, numRowGroupsPruned for
../benchmarks/parquet/lineitem/part-0.parquet=0] |
+-------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set. Query took 0.071 seconds.
> explain analyze select max(l_partkey) from lineitem;
+-------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| plan_type | plan
|
+-------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Plan with Metrics | ProjectionExec: expr=[MAX(lineitem.l_partkey)@0 as
MAX(l_partkey)], metrics=[]
|
| | HashAggregateExec: mode=Final, gby=[],
aggr=[MAX(l_partkey)], metrics=[outputRows=0]
|
| | CoalescePartitionsExec, metrics=[]
|
| | HashAggregateExec: mode=Partial, gby=[],
aggr=[MAX(l_partkey)], metrics=[outputRows=0]
|
| | RepartitionExec:
partitioning=RoundRobinBatch(16), metrics=[fetchTime=51231297,
repartitionTime=0, sendTime=120310]
|
| | ParquetExec: batch_size=8192, limit=None,
partitions=[../benchmarks/parquet/lineitem/part-0.parquet],
metrics=[numPredicateCreationErrors=0, numPredicateEvaluationErrors for
../benchmarks/parquet/lineitem/part-0.parquet=0, numRowGroupsPruned for
../benchmarks/parquet/lineitem/part-0.parquet=0] |
+-------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set. Query took 0.071 seconds.
```
**To Reproduce**
run some queries with explain vs explain analyze.
**Expected behavior**
explain analyze should have same plans
**Additional context**
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