[DRILL-5959] Unable to apply Union on multiple select query expressions

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.10.0, 1.11.0
• Fix Version/s: Future
• Component/s: Client - JDBC
• Assignee: Unassigned
• Reporter: Rajeshwar Rao
• Created: 13/Nov/17 10:40
• Updated: 09/Apr/18 11:20

Description

Unable to combine the result sets of more than two separate query expressions

example :

select color, Paul , 'Paul' name
from mysql.devcdp25.pivtest
union all
select color, John , 'John' name
from mysql.devcdp25.pivtest
union all
select color, Tim , 'Tim' name
from mysql.devcdp25.pivtest

Query Failed: An Error Occurred
org.apache.drill.common.exceptions.UserRemoteException: DATA_READ ERROR: The JDBC storage plugin failed while trying setup the SQL query. sql SELECT * FROM (SELECT `color`, `Paul`, 'Paul' AS `name` FROM `devcdp25`.`pivtest` UNION ALL SELECT `color`, `John`, 'John' AS `name` FROM `devcdp25`.`pivtest`) UNION ALL SELECT `color`, `Tim`, 'Tim' AS `name` FROM `devcdp25`.`pivtest` plugin mysql Fragment 0:0

it is desirable to support combining multiple result sets in a single query
note: the same works fine in MySQL