[SPARK-27903] Improve parser error message for mismatched parentheses in expressions

• Type: Sub-task
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 3.0.0
• Component/s: SQL
• Assignee: Unassigned
• Reporter: Yesheng Ma
• Created: 31/May/19 17:45
• Updated: 09/Jan/20 15:30

Description

When parentheses are mismatched in expressions in queries, the error message is confusing. This is especially true for large queries, where mismatched parens are tedious for human to figure out.

For example, the error message for

 
SELECT ((x + y) * z FROM t; 

is

 
mismatched input 'FROM' expecting ','(line 1, pos 20) 

One possible way to fix is to explicitly capture such kind of mismatched parens in a grammar rule and print user-friendly error message such as

 
mismatched parentheses for expression 'SELECT ((x + y) * z FROM t;'(line 1, pos 20) 

Issue Links

• links to: GitHub Pull Request #26144