drill-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Muhammad Gelbana <m.gelb...@gmail.com>
Subject FindHardDistributionScans throws a NPE while visiting a TableScan
Date Mon, 19 Jun 2017 21:19:18 GMT
Everyone,

I made a copy of the Jdbc plugin and made modifications to it by adding a
few rules. None of the modification I made or the rules I wrote should have
anything extra to do with handling the following SQL query

SELECT * FROM incorta.SALES.SALES SALES WHERE 1 = 2 LIMIT 1


I know the query is useless, but I need to to know how to fix the following
error thrown while handling this query. This is the final query plan:

DEBUG o.a.d.e.p.s.h.DefaultSqlHandler - HEP_BOTTOM_UP:Convert SUM to $SUM0
> (0ms):
> DrillLimitRel(*fetch=[1]*): rowcount = 1.0, cumulative cost = {201.0
> rows, 205.0 cpu, 0.0 io, 0.0 network, 0.0 memory}, id = 2653
>   DrillLimitRel(*offset=[0], fetch=[0]*): rowcount = 1.0, cumulative cost
> = {200.0 rows, 201.0 cpu, 0.0 io, 0.0 network, 0.0 memory}, id = 2651
>     GelbanaJdbcDrel: rowcount = 100.0, cumulative cost = {200.0 rows,
> 201.0 cpu, 0.0 io, 0.0 network, 0.0 memory}, id = 2649
>       JdbcTableScan(table=[[gelbana, SALES, SALES]]): rowcount = 100.0,
> cumulative cost = {100.0 rows, 101.0 cpu, 0.0 io, 0.0 network, 0.0 memory},
> id = 2572


This is the throw error stacktrace

[Error Id: 83ea094a-db24-4d6d-bf0d-271db26db933 on 640fb7ebbd1a:31010]
at
org.apache.drill.common.exceptions.UserException$Builder.build(UserException.java:543)
~[drill-common-1.9.0.jar:1.9.0]
at
org.apache.drill.exec.work.foreman.Foreman$ForemanResult.close(Foreman.java:825)
[drill-java-exec-1.9.0.jar:1.9.0]
at org.apache.drill.exec.work.foreman.Foreman.moveToState(Foreman.java:935)
[drill-java-exec-1.9.0.jar:1.9.0]
at org.apache.drill.exec.work.foreman.Foreman.run(Foreman.java:281)
[drill-java-exec-1.9.0.jar:1.9.0]
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
[na:1.8.0_131]
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
[na:1.8.0_131]
at java.lang.Thread.run(Thread.java:748) [na:1.8.0_131]
Caused by: org.apache.drill.exec.work.foreman.ForemanException: Unexpected
exception during fragment initialization: null
... 4 common frames omitted
*Caused by: java.lang.NullPointerException: null*
at
org.apache.drill.exec.planner.sql.handlers.FindHardDistributionScans.visit(FindHardDistributionScans.java:55)
~[drill-java-exec-1.9.0.jar:1.9.0]
at org.apache.calcite.rel.core.TableScan.accept(TableScan.java:166)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at org.apache.calcite.rel.RelShuttleImpl.visitChild(RelShuttleImpl.java:53)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at
org.apache.calcite.rel.RelShuttleImpl.visitChildren(RelShuttleImpl.java:68)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at org.apache.calcite.rel.RelShuttleImpl.visit(RelShuttleImpl.java:126)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at org.apache.calcite.rel.AbstractRelNode.accept(AbstractRelNode.java:256)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at org.apache.calcite.rel.RelShuttleImpl.visitChild(RelShuttleImpl.java:53)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at
org.apache.calcite.rel.RelShuttleImpl.visitChildren(RelShuttleImpl.java:68)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at org.apache.calcite.rel.RelShuttleImpl.visit(RelShuttleImpl.java:126)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at org.apache.calcite.rel.AbstractRelNode.accept(AbstractRelNode.java:256)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at org.apache.calcite.rel.RelShuttleImpl.visitChild(RelShuttleImpl.java:53)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at
org.apache.calcite.rel.RelShuttleImpl.visitChildren(RelShuttleImpl.java:68)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at org.apache.calcite.rel.RelShuttleImpl.visit(RelShuttleImpl.java:126)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at org.apache.calcite.rel.AbstractRelNode.accept(AbstractRelNode.java:256)
~[calcite-core-1.4.0-drill-r19.jar:1.4.0-drill-r19]
at
org.apache.drill.exec.planner.sql.handlers.FindHardDistributionScans.canForceSingleMode(FindHardDistributionScans.java:45)
~[drill-java-exec-1.9.0.jar:1.9.0]
at
org.apache.drill.exec.planner.sql.handlers.DefaultSqlHandler.convertToDrel(DefaultSqlHandler.java:262)
~[drill-java-exec-1.9.0.jar:1.9.0]
at
org.apache.drill.exec.planner.sql.handlers.DefaultSqlHandler.convertToDrel(DefaultSqlHandler.java:290)
~[drill-java-exec-1.9.0.jar:1.9.0]
at
org.apache.drill.exec.planner.sql.handlers.DefaultSqlHandler.getPlan(DefaultSqlHandler.java:168)
~[drill-java-exec-1.9.0.jar:1.9.0]
at
org.apache.drill.exec.planner.sql.DrillSqlWorker.getPhysicalPlan(DrillSqlWorker.java:123)
~[drill-java-exec-1.9.0.jar:1.9.0]
at
org.apache.drill.exec.planner.sql.DrillSqlWorker.getPlan(DrillSqlWorker.java:97)
~[drill-java-exec-1.9.0.jar:1.9.0]
at org.apache.drill.exec.work.foreman.Foreman.runSQL(Foreman.java:1008)
[drill-java-exec-1.9.0.jar:1.9.0]
at org.apache.drill.exec.work.foreman.Foreman.run(Foreman.java:264)
[drill-java-exec-1.9.0.jar:1.9.0]
... 3 common frames omitted

Whic is because this statement

unwrap =
> scan.getTable().unwrap(DrillTranslatableTable.class).getDrillTable();


In *FindHardDistributionScans.java:55* evaluates
*scan.getTable().unwrap(DrillTranslatableTable.class)* to null

Would someone please explain to me what is Drill trying to do and what did
I do wrong ?

*---------------------*
*Muhammad Gelbana*
http://www.linkedin.com/in/mgelbana

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message