Remove unnecessary DFSchema::check_ambiguous_name (#12805)

Author: jonahgao

datafusion/common/src/dfschema.rs

@@ -406,33 +406,6 @@ impl DFSchema {
         }
     }
 
-    /// Check whether the column reference is ambiguous
-    pub fn check_ambiguous_name(
-        &self,
-        qualifier: Option<&TableReference>,
-        name: &str,
-    ) -> Result<()> {
-        let count = self
-            .iter()
-            .filter(|(field_q, f)| match (field_q, qualifier) {
-                (Some(q1), Some(q2)) => q1.resolved_eq(q2) && f.name() == name,
-                (None, None) => f.name() == name,
-                _ => false,
-            })
-            .take(2)
-            .count();
-        if count > 1 {
-            _schema_err!(SchemaError::AmbiguousReference {
-                field: Column {
-                    relation: None,
-                    name: name.to_string(),
-                },
-            })
-        } else {
-            Ok(())
-        }
-    }
-
     /// Find the qualified field with the given name
     pub fn qualified_field_with_name(
         &self,

datafusion/sql/src/expr/identifier.rs

@@ -126,9 +126,6 @@ impl<'a, S: ContextProvider> SqlToRel<'a, S> {
                         ) {
                             match planner_result {
                                 PlannerResult::Planned(expr) => {
-                                    // sanity check on column
-                                    schema
-                                        .check_ambiguous_name(qualifier, field.name())?;
                                     return Ok(expr);
                                 }
                                 PlannerResult::Original(_args) => {}
@@ -139,8 +136,6 @@ impl<'a, S: ContextProvider> SqlToRel<'a, S> {
                 }
                 // found matching field with no spare identifier(s)
                 Some((field, qualifier, _nested_names)) => {
-                    // sanity check on column
-                    schema.check_ambiguous_name(qualifier, field.name())?;
                     Ok(Expr::Column(Column::from((qualifier, field))))
                 }
                 None => {
@@ -184,9 +179,6 @@ impl<'a, S: ContextProvider> SqlToRel<'a, S> {
                             let s = &ids[0..ids.len()];
                             // safe unwrap as s can never be empty or exceed the bounds
                             let (relation, column_name) = form_identifier(s).unwrap();
-                            // sanity check on column
-                            schema
-                                .check_ambiguous_name(relation.as_ref(), column_name)?;
                             Ok(Expr::Column(Column::new(relation, column_name)))
                         }
                     }