use datafusion::error::Result;
use datafusion::prelude::SessionContext;
use datafusion::sql::unparser::Unparser;
use datafusion::sql::unparser::dialect::PostgreSqlDialect;

#[tokio::main]
async fn main() -> Result<()> {
    let ctx = SessionContext::new();

    ctx.sql("create table test (k int, v int)")
        .await?
        .collect()
        .await?;

    let df = ctx.sql("select t1.v, t2.v from test t1, test t2").await?;

    println!("{}\n", df.logical_plan());

    let plan = df.into_optimized_plan()?;
    println!("{}\n", plan);

    println!(
        "{}",
        Unparser::new(&PostgreSqlDialect {})
            .plan_to_sql(&plan)
            .unwrap()
    );

    Ok(())
}