Details
-
Bug
-
Status: Closed
-
Major
-
Resolution: Fixed
-
None
-
None
Description
Pruning fails for this query:
0: jdbc:drill:zk=local> explain plan for select count(*) from dfs.`/Users/asinha/data/multilevel/parquet` where dir0 = 1994 and coalesce(o_clerk, 'Clerk') = ''; +------+------+ | text | json | +------+------+ | 00-00 Screen 00-01 Project(EXPR$0=[$0]) 00-02 StreamAgg(group=[{}], EXPR$0=[COUNT()]) 00-03 Project($f0=[0]) 00-04 SelectionVectorRemover 00-05 Filter(condition=[AND(=($0, 1994), =(CASE(IS NOT NULL($1), $1, 'Clerk'), ''))]) 00-06 Scan(groupscan=[ParquetGroupScan [entries=[ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1994/Q1/orders_94_q1.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1994/Q2/orders_94_q2.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1994/Q3/orders_94_q3.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1994/Q4/orders_94_q4.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1995/Q1/orders_95_q1.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1995/Q2/orders_95_q2.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1995/Q3/orders_95_q3.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1995/Q4/orders_95_q4.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1996/Q1/orders_96_q1.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1996/Q2/orders_96_q2.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1996/Q3/orders_96_q3.parquet], ReadEntryWithPath [path=file:/Users/asinha/data/multilevel/parquet/1996/Q4/orders_96_q4.parquet]], selectionRoot=file:/Users/asinha/data/multilevel/parquet, numFiles=12, usedMetadataFile=false, columns=[`dir0`, `o_clerk`]]])
The log indicates no partition filters were found:
...
o.a.d.e.p.l.partition.PruneScanRule - No conditions were found eligible for partition pruning.Total pruning elapsed time: 0 ms
A preliminary analysis indicates that since the Coalesce gets converted to a CASE(IS NOT NULL....) expression, the filter analysis does not correctly process the full expression tree. At one point in FindPartitionConditions.analyzeCall() I saw the operandStack had 3 elements in it: [NO_PUSH, NO_PUSH, PUSH] which seemed strange since I would expect even number of elements.