[DRILL-3412] Projections are not getting push down below Window operator

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Fix Version/s: 1.2.0
• Component/s: Query Planning & Optimization
• Labels: window_function
• Assignee: Sean Hsuan-Yi Chu
• Reporter: Aman Sinha
• Created: 28/Jun/15 01:47
• Updated: 15/Sep/15 00:44
• Resolved: 11/Sep/15 05:41

Description

The plan below shows that the 'star' column is being produced by the Scan and subsequent Project. This indicates projection pushdown is not working as desired when window function is present. The query produces correct results.

explain plan for select min(n_nationkey) over (partition by n_regionkey) from cp.`tpch/nation.parquet` ;
00-00    Screen
00-01      Project(EXPR$0=[$0])
00-02        Project(w0$o0=[$3])
00-03          Window(window#0=[window(partition {2} order by [] range between UNBOUNDED PRECEDING and UNBOUNDED FOLLOWING aggs [MIN($1)])])
00-04            SelectionVectorRemover
00-05              Sort(sort0=[$2], dir0=[ASC])
00-06                Project(T1¦¦*=[$0], n_nationkey=[$1], n_regionkey=[$2])
00-07                  Scan(groupscan=[ParquetGroupScan [entries=[ReadEntryWithPath [path=classpath:/tpch/nation.parquet]], selectionRoot=/tpch/nation.parquet, numFiles=1, columns=[`*`]]])

Issue Links

• relates to: DRILL-3683 [Unit Test] Add expected plan for tests in TestWindowFunctions suite