Schema Inference For Projections With and Without Alias

[am357]

According to the findings by the experimental implementation work for Schema Inferencer In PartiQL Rust the following questions need to get answered by the PartiQL Type System spec. work:

Let both customers and details have open schemas. In Strict typing mode, what should be the output schema of the following query?

-- customers: <<{'id': INT, 'name': STRING, 'details': {'age': INT}}>>
SELECT d.age FROM customers.details AS d;

In addition, what should be the inference rule for SELECT d.age +1 FROM customers.details AS d?

Some Intuitive options:

1. Use age as in <<{'age': INT}>>
2. Use d.age as in <<{'d.age': INT}>>
3. Use d as in `<<{'d': INT}>>

See @jpschorr comment: partiql/partiql-lang-rust#399