Function replace_columns

datafusion/expr/src/logical_plan/builder.rs:2033–2049

If there is a REPLACE statement in the projected expression in the form of "REPLACE (some_column_within_an_expr AS some_column)", this function replaces that column with the given replace expression. Column name remains the same. Multiple REPLACEs are also possible with comma separations.

(
    mut exprs: Vec<Expr>,
    replace: &PlannedReplaceSelectItem,
)

/// that column with the given replace expression. Column name remains the same.
/// Multiple REPLACEs are also possible with comma separations.
fn replace_columns(
    mut exprs: Vec<Expr>,
    replace: &PlannedReplaceSelectItem,
) -> Result<Vec<Expr>> {
    for expr in exprs.iter_mut() {
        if let Expr::Column(Column { name, .. }) = expr
            && let Some((_, new_expr)) = replace
                .items()
                .iter()
                .zip(replace.expressions().iter())
                .find(|(item, _)| item.column_name.value == *name)
        {
            *expr = new_expr.clone().alias(name.clone())
        }
    }
    Ok(exprs)
}

/// Create a SubqueryAlias to wrap a LogicalPlan.
pub fn subquery_alias(