Need Query Parser Support

[adityamatt]

Hi,

We have a use case where we want to know the tables/schemas dependencies of a Presto Query.
The package provides a way to query the presto db with an actual query which would actually execute the query, but instead I'm looking for query parser support. We have such support in java but not in typescript.

[yhwang]

When implementing the SQL Client of the Presto UI, I tried several SQL parsers from the NPM repo, but they don't work well with Presto SQL. Presto SQL is compliant with ANSI SQL, however, it still has some unique formats in some entities, like a fully qualified table name is using <catalog>.<scheme>.<table name> format, and most parsers don't support it.

So my solution is to generate the SQL Parser from the ANTLR grammar file that Presto is using: https://github.com/prestodb/presto/blob/master/presto-parser/src/main/antlr4/com/facebook/presto/sql/parser/SqlBase.g4

You can check details here: https://github.com/prestodb/presto/tree/master/presto-main/src/main/resources/webapp/src/sql-parser and antlr4 supports TypeScript too. You just need to get familiar with the Lexer, Listener, and Parser concepts in ANTLR to use the parser it generates.

If people do need a js SQL parser for Presto SQL, it would be good to automate the process to:

• generate the ANTLR Lexer, Listener, and Parser for TypeScript from Presto SQL grammar
• publish the files as a presto-sql-parser (like @prestodb/presto-sql-parser) NPM module

Once there is any change in the grammar file, the new parser will be generated and published.

[adityamatt]

Thanks for pointing out a solution, I'll update the thread once I try it out