Function check_columns_satisfy_exprs

datafusion/sql/src/utils.rs:135–168

Determines if the set of `Expr`'s are a valid projection on the input `Expr::Column`'s.

(
    columns: &[Expr],
    exprs: &[Expr],
    purpose: CheckColumnsSatisfyExprsPurpose,
)

/// Determines if the set of `Expr`'s are a valid projection on the input
/// `Expr::Column`'s.
pub(crate) fn check_columns_satisfy_exprs(
    columns: &[Expr],
    exprs: &[Expr],
    purpose: CheckColumnsSatisfyExprsPurpose,
) -> Result<()> {
    columns.iter().try_for_each(|c| match c {
        Expr::Column(_) => Ok(()),
        _ => internal_err!("Expr::Column are required"),
    })?;
    let column_exprs = find_column_exprs(exprs);
    for e in &column_exprs {
        match e {
            Expr::GroupingSet(GroupingSet::Rollup(exprs)) => {
                for e in exprs {
                    check_column_satisfies_expr(columns, e, purpose)?;
                }
            }
            Expr::GroupingSet(GroupingSet::Cube(exprs)) => {
                for e in exprs {
                    check_column_satisfies_expr(columns, e, purpose)?;
                }
            }
            Expr::GroupingSet(GroupingSet::GroupingSets(lists_of_exprs)) => {
                for exprs in lists_of_exprs {
                    for e in exprs {
                        check_column_satisfies_expr(columns, e, purpose)?;
                    }
                }
            }
            _ => check_column_satisfies_expr(columns, e, purpose)?,
        }
    }
    Ok(())
}

fn check_column_satisfies_expr(
    columns: &[Expr],