#[tokio::test]
async fn select_all() -> Result<()> {
    // build plan using `select_expr``
    let t = test_table().await?;

    let df = t
    .select(vec![wildcard()])?;

    let plan = df
        .logical_plan().clone();
    
    let r = df.collect().await?;
    println!("r: {:?}", r);


    println!("paln: {}", plan.display_indent());

    Ok(())
}

impl Projection {
    pub fn try_new_with_schema(
        expr: Vec<Expr>,
        wildcard: Option<WildcardOptions>,
        input: Arc<LogicalPlan>,
        schema: DFSchemaRef,
    ) -> Result<Self>

enum ProjectionExprs {
    /// The expressions are provided as a list of expressions
    Exprs(Vec<Expr>),
    /// The expressions are provided as a wildcard
    Wildcard(WildcardOptions),
}