[SPARK-19472] [SQL]SQLParser fails to resolve nested CASE WHEN statement with parentheses

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.0
• Fix Version/s: 2.0.3, 2.1.1, 2.2.0
• Component/s: SQL
• Assignee: Herman van Hövell
• Reporter: StanZhai
• Created: 06/Feb/17 04:39
• Updated: 06/Feb/17 20:30
• Resolved: 06/Feb/17 20:30

Description

SQLParser fails to resolve nested CASE WHEN statement like this:

select case when
(1) +
case when 1>0 then 1 else 0 end = 2
then 1 else 0 end
from tb

==================== Exception ====================
Exception in thread "main" org.apache.spark.sql.catalyst.parser.ParseException:
mismatched input 'then' expecting

{'.', '[', 'OR', 'AND', 'IN', NOT, 'BETWEEN', 'LIKE', RLIKE, 'IS', 'WHEN', EQ, '<=>', '<>', '!=', '<', LTE, '>', GTE, '+', '-', '*', '/', '%', 'DIV', '&', '|', '^'}

(line 5, pos 0)

== SQL ==

select case when
(1) +
case when 1>0 then 1 else 0 end = 2
then 1 else 0 end
^^^
from tb

But，remove parentheses will be fine：

select case when
1 +
case when 1>0 then 1 else 0 end = 2
then 1 else 0 end
from tb

Issue Links

• links to: [Github] Pull Request #16821 (hvanhovell)