Presto SQL Parser Now Supports Trailing Commas #23927
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Description
This pull request adds support for "trailing commas" in the SQL parser for Presto. This change allows users to include a trailing comma in their SELECT statements, aligning with the style supported by other SQL engines.
Motivation and Context
The change is motivated by two main reasons:
This change addresses the issue "Support Google-style trailing comma in SELECT". Allowing trailing commas is a minor deviation from ANSI SQL, but it aligns with the style adopted by many programming languages like Python, Rust, and TypeScript, which enhances usability and reduces syntax errors.
Impact
This change introduces a new feature in the SQL parser, allowing trailing commas in SELECT statements. It does not affect existing functionality and is backward compatible.
Test Plan
The change has been tested by adding unit tests that cover various scenarios involving trailing commas in SELECT statements. These tests ensure that the parser correctly handles the new syntax without introducing regressions.
Contributor checklist