From bd9e37d9cd0694ed88d0955013a7cf600b0544c6 Mon Sep 17 00:00:00 2001
From: Jia-Xuan Liu <liugs963@gmail.com>
Date: Fri, 26 Jul 2024 23:03:02 +0800
Subject: [PATCH] allow qualified wildcard expressions to exist in the logical
 plan

---
 datafusion/expr/src/expr.rs        |  4 +---
 datafusion/expr/src/expr_schema.rs | 21 +++++----------------
 2 files changed, 6 insertions(+), 19 deletions(-)

diff --git a/datafusion/expr/src/expr.rs b/datafusion/expr/src/expr.rs
index 68d5504eea48..7f82337e1b45 100644
--- a/datafusion/expr/src/expr.rs
+++ b/datafusion/expr/src/expr.rs
@@ -2305,9 +2305,7 @@ fn write_name<W: Write>(w: &mut W, e: &Expr) -> Result<()> {
         }
         Expr::Wildcard { qualifier } => match qualifier {
             Some(qualifier) => {
-                return internal_err!(
-                    "Create name does not support qualified wildcard, got {qualifier}"
-                )
+                write!(w, "{}.*", qualifier)?;
             }
             None => write!(w, "*")?,
         },
diff --git a/datafusion/expr/src/expr_schema.rs b/datafusion/expr/src/expr_schema.rs
index 5e0571f712ee..d3648a722d4c 100644
--- a/datafusion/expr/src/expr_schema.rs
+++ b/datafusion/expr/src/expr_schema.rs
@@ -28,8 +28,8 @@ use crate::{utils, LogicalPlan, Projection, Subquery, WindowFunctionDefinition};
 use arrow::compute::can_cast_types;
 use arrow::datatypes::{DataType, Field};
 use datafusion_common::{
-    internal_err, not_impl_err, plan_datafusion_err, plan_err, Column, ExprSchema,
-    Result, TableReference,
+    not_impl_err, plan_datafusion_err, plan_err, Column, ExprSchema, Result,
+    TableReference,
 };
 use std::collections::HashMap;
 use std::sync::Arc;
@@ -254,13 +254,7 @@ impl ExprSchemable for Expr {
                     )
                 })
             }
-            Expr::Wildcard { qualifier } => {
-                // Wildcard do not really have a type and do not appear in projections
-                match qualifier {
-                    Some(_) => internal_err!("QualifiedWildcard expressions are not valid in a logical query plan"),
-                    None => Ok(DataType::Null)
-                }
-            }
+            Expr::Wildcard { .. } => Ok(DataType::Null),
             Expr::GroupingSet(_) => {
                 // grouping sets do not really have a type and do not appear in projections
                 Ok(DataType::Null)
@@ -374,12 +368,7 @@ impl ExprSchemable for Expr {
             | Expr::SimilarTo(Like { expr, pattern, .. }) => {
                 Ok(expr.nullable(input_schema)? || pattern.nullable(input_schema)?)
             }
-            Expr::Wildcard { qualifier } => match qualifier {
-                Some(_) => internal_err!(
-                    "QualifiedWildcard expressions are not valid in a logical query plan"
-                ),
-                None => Ok(false),
-            },
+            Expr::Wildcard { .. } => Ok(false),
             Expr::GroupingSet(_) => {
                 // grouping sets do not really have the concept of nullable and do not appear
                 // in projections
@@ -560,7 +549,7 @@ mod tests {
     use super::*;
     use crate::{col, lit};
 
-    use datafusion_common::{DFSchema, ScalarValue};
+    use datafusion_common::{internal_err, DFSchema, ScalarValue};
 
     macro_rules! test_is_expr_nullable {
         ($EXPR_TYPE:ident) => {{