From: Tom Lane <tgl@sss.pgh.pa.us>
To: walther@technowledgy.de
cc: =?UTF-8?B?Sm9zZWYgxaBpbcOhbmVr?= <josef.simanek@gmail.com>,
        Robert Haas <robertmhaas@gmail.com>,
        Tomas Vondra <tomas.vondra@enterprisedb.com>,
        "David G. Johnston" <david.g.johnston@gmail.com>,
        Laurenz Albe <laurenz.albe@cybertec.at>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: [PATCH] Add --syntax to postgres for SQL syntax checking
In-reply-to: <43eeedd7-51a6-4520-8848-247341566e3d@technowledgy.de>
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Comments: In-reply-to walther@technowledgy.de
	message dated "Wed, 15 May 2024 20:49:17 +0200"
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Date: Wed, 15 May 2024 15:01:25 -0400
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walther@technowledgy.de writes:
> Tom Lane:
>> BTW, if you do feel that a pure grammar check is worthwhile, you
>> should look at the ecpg preprocessor, which does more or less that
>> with the SQL portions of its input.

> Would working with ecpg allow to get back a parse tree of the query to 
> do stuff with that?

No, ecpg isn't interested in building a syntax tree.

> This is really what is missing for the ecosystem. A libpqparser for 
> tools to use: Formatters, linters, query rewriters, simple syntax 
> checkers... they are all missing access to postgres' own parser.

To get to that, you'd need some kind of agreement on what the syntax
tree is.  I doubt our existing implementation would be directly useful
to very many tools, and even if it is, do they want to track constant
version-to-version changes?

			regards, tom lane