[DRILL-4700] physical plan in multiple Unions with jdbc storage with derived table without alias

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.6.0
• Component/s: SQL Parser, Storage - JDBC
• Assignee: Unassigned
• Reporter: Miguel Lamy
• Created: 31/May/16 18:26
• Updated: 07/Jun/16 10:23

Description

The problem occurs when there is more than one union in the query using jdbc storage.

This query works:
0: jdbc:drill:zk=local> select 0 a from (values(1))
. . . . . . . . . . . > union all
. . . . . . . . . . . > select 1 a from (values(1))
. . . . . . . . . . . > union all
. . . . . . . . . . . > select 2 a from (values(1));
----

a

----

0

1

2

----

This query using mysql storage or mssql storage doesn't work:

0: jdbc:drill:zk=local> select 0 as ChvOutTerc from ProcessarReceita procrec0
. . . . . . . . . . . > union all
. . . . . . . . . . . > select 1 as ChvOutTerc from ProcessarReceita procrec1
. . . . . . . . . . . > union all
. . . . . . . . . . . > select 2 as ChvOutTerc from ProcessarReceita procrec2;
Error: DATA_READ ERROR: The JDBC storage plugin failed while trying setup the SQL query.

sql SELECT *
FROM (SELECT 0 AS "ChvOutTerc"
FROM "dbo"."ProcessarReceita"
UNION ALL
SELECT 1 AS "ChvOutTerc"
FROM "dbo"."ProcessarReceita")
UNION ALL
SELECT 2 AS "ChvOutTerc"
FROM "dbo"."ProcessarReceita"
plugin siag_enidh
Fragment 0:0

[Error Id: f3afa6ce-895c-4aa3-bfda-b769e4795ae1 on hefesto.siag.pt:31010] (state=,code=0)

Changing the physical plan to include an alias on derived table and then executing that physical plan works without problem:

SELECT *
FROM (SELECT 0 AS "ChvOutTerc"
FROM "dbo"."ProcessarReceita"
UNION ALL
SELECT 1 AS "ChvOutTerc"
FROM "dbo"."ProcessarReceita") mytable
UNION ALL
SELECT 2 AS "ChvOutTerc"
FROM "dbo"."ProcessarReceita"

Also tested with 1.7.0-SNAPSHOT (20160531) with the same results.

Results with just one union:

0: jdbc:drill:zk=local> select 0 as ChvOutTerc from ProcessarReceita procrec0
. . . . . . . . . . . > union all
. . . . . . . . . . . > select 1 as ChvOutTerc from ProcessarReceita procrec1 limit 3;
-------------

ChvOutTerc

-------------

0

0

0

-------------
3 rows selected (0.708 seconds)
0: jdbc:drill:zk=local> select 1 as ChvOutTerc from ProcessarReceita procrec1
. . . . . . . . . . . > union all
. . . . . . . . . . . > select 2 as ChvOutTerc from ProcessarReceita procrec2 limit 3;
-------------

ChvOutTerc

-------------

1

1

1

-------------
3 rows selected (0.449 seconds)

Update: The query with multi unions works with Oracle jdbc driver.