Transpiling from SQL to PRQL about prql

[ryanrussell]

A SQL -> PRQL transpiler would REALLY ease adoption for PRQL.

Even if it had some disclaimers, it lowers a lot of barriers if a new user is trying to learn/adopt PRQL and could copy/paste a bunch of SQL queries.

[aljazerzen]

Update: this is currently not possible yet, but we are not far off.

The Display trait for prql's AST Node is done, we just need to parse SQL and convert it to AST, which should't be a major problem.

[florent-martineau]

Using Apache Calcite for parsing queries and turning them into an AST could be an idea.

Calcite is written in Java, though, and not in Rust.

[max-sixty]

We'd likely use sqlparser-rs, which we currently use to represent SQL AST, and it builds the SQL string.