Function where_in_subquery

datafusion-examples/examples/dataframe/dataframe.rs:297–318

Use the DataFrame API to execute the following subquery: select t1.car, t1.speed from t1 where t1.speed in (select max(t2.speed) from t2 where t2.car = 'red') limit 3;

(ctx: &SessionContext)

/// Use the DataFrame API to execute the following subquery:
/// select t1.car, t1.speed from t1 where t1.speed in (select max(t2.speed) from t2 where t2.car = 'red') limit 3;
async fn where_in_subquery(ctx: &SessionContext) -> Result<()> {
    ctx.table("t1")
        .await?
        .filter(in_subquery(
            col("t1.speed"),
            Arc::new(
                ctx.table("t2")
                    .await?
                    .filter(
                        col("t2.car").eq(lit(ScalarValue::Utf8(Some("red".to_string())))),
                    )?
                    .aggregate(vec![], vec![max(col("t2.speed"))])?
                    .select(vec![max(col("t2.speed"))])?
                    .into_unoptimized_plan(),
            ),
        ))?
        .select(vec![col("t1.car"), col("t1.speed")])?
        .limit(0, Some(3))?
        .show()
        .await?;
    Ok(())
}

/// Use the DataFrame API to execute the following subquery:
/// select t1.car, t1.speed from t1 where exists (select t2.speed from t2 where t1.car = t2.car) limit 3;