feat(trino): Support JSON_QUERY

[VaggelisD]

Fixes #4200

This PR adds parsing support for Trino's JSON_QUERY(...) which is a more powerful version of JSON_EXTRACT(...).

For this matter, exp.JSONExtract node is reused, but to differentiate between the two a new arg is introduced; This is also required because Presto's jsonextract_sql has the variant_access logic which must be preserved for Trino.

Docs

JSON_QUERY | JSON_EXTRACT

[georgesittas]

What are the advantages of treating this as JSONExtract? Other dialects also support JSON_QUERY, possibly with similar semantics. Check T-SQL for example.

[VaggelisD]

@georgesittas For Trino, JSON_EXTRACT and JSON_QUERY are semantically equivalent with the exception that JSON_QUERY allows for more options baked-in; Splitting these two to separate nodes would duplicate a lot of code for no particular reason as it stands. My guess is that the former is the Presto-compatible API while the latter is Trino specific as I couldn't find it in Presto's docs.

Afaict, for other dialects like T-SQL JSON_QUERY is just the equivalent function for extraction so I'm also not sure if there are any nuances that justify splitting these two for now. Wdyt?

[georgesittas]

@georgesittas For Trino, JSON_EXTRACT and JSON_QUERY are semantically equivalent with the exception that JSON_QUERY allows for more options baked-in; Splitting these two to separate nodes would duplicate a lot of code for no particular reason as it stands. My guess is that the former is the Presto-compatible API while the latter is Trino specific as I couldn't find it in Presto's docs.

Not sure if this is true, I think there are some differences. For example, there's a path that looks like 'lax $.children[*]' in Trino's docs. I don't remember needing to specify lax or strict in JSON_EXTRACT. Also, at least in T-SQL (perhaps others too), JSON_QUERY only extracts nested values, and you need to use JSON_VALUE for literals. So I don't think this is accurate:

Afaict, for other dialects like T-SQL JSON_QUERY is just the equivalent function for extraction so I'm also not sure if there are any nuances that justify splitting these two for now. Wdyt?

[VaggelisD]

Not sure if this is true, I think there are some differences.

Right, I consider these extra options but at the end both JSON_EXTRACT and JSON_QUERY extract JSON values so I don't see the dire need to split them apart yet.

Also, at least in T-SQL (perhaps others too), JSON_QUERY only extracts nested values

For T-SQL you'd indeed need JSON_VALUE for scalar values but that'd be exp.JSONExtractScalar, right?

Also, in SQLGlot today T-SQL is the only other dialect which has JSON_QUERY

[georgesittas]

For T-SQL you'd indeed need JSON_VALUE for scalar values but that'd be exp.JSONExtractScalar, right?

Not exactly. Take these T-SQL expressions, for example:

1> select json_query('{"x": 1}', '$.x')
2> GO -- yields NULL
3> select json_query('{"x": [1,2,3]}', '$.x')
4> GO -- yields [1,2,3]
5> select json_value('{"x": 1}', '$.x')
6> GO -- yields 1