Function create_col_from_scalar_expr

datafusion/expr/src/expr_rewriter/mod.rs:177–195

Create a Column from the Scalar Expr

(
    scalar_expr: &Expr,
    subqry_alias: String,
)

/// Create a Column from the Scalar Expr
pub fn create_col_from_scalar_expr(
    scalar_expr: &Expr,
    subqry_alias: String,
) -> Result<Column> {
    match scalar_expr {
        Expr::Alias(Alias { name, .. }) => Ok(Column::new(
            Some::<TableReference>(subqry_alias.into()),
            name,
        )),
        Expr::Column(col) => Ok(col.with_relation(subqry_alias.into())),
        _ => {
            let scalar_column = scalar_expr.schema_name().to_string();
            Ok(Column::new(
                Some::<TableReference>(subqry_alias.into()),
                scalar_column,
            ))
        }
    }
}

/// Recursively un-normalize all [`Column`] expressions in a list of expression trees
#[inline]