Return err if wildcard is not expanded before type coercion

datafusion/optimizer/src/analyzer/type_coercion.rs

@@ -995,16 +995,19 @@ fn project_with_column_index(
         .enumerate()
         .map(|(i, e)| match e {
             Expr::Alias(Alias { ref name, .. }) if name != schema.field(i).name() => {
-                e.unalias().alias(schema.field(i).name())
+                Ok(e.unalias().alias(schema.field(i).name()))
             }
             Expr::Column(Column {
                 relation: _,
                 ref name,
-            }) if name != schema.field(i).name() => e.alias(schema.field(i).name()),
-            Expr::Alias { .. } | Expr::Column { .. } => e,
-            _ => e.alias(schema.field(i).name()),
+            }) if name != schema.field(i).name() => Ok(e.alias(schema.field(i).name())),
+            Expr::Alias { .. } | Expr::Column { .. } => Ok(e),
+            Expr::Wildcard { .. } => {
+                plan_err!("Wildcard should be expanded before type coercion")
+            }
+            _ => Ok(e.alias(schema.field(i).name())),
         })
-        .collect::<Vec<_>>();
+        .collect::<Result<Vec<_>>>()?;
 
     Projection::try_new_with_schema(alias_expr, input, schema)
         .map(LogicalPlan::Projection)
@@ -1018,6 +1021,10 @@ mod test {
     use arrow::datatypes::DataType::Utf8;
     use arrow::datatypes::{DataType, Field, TimeUnit};
 
+    use crate::analyzer::type_coercion::{
+        coerce_case_expression, TypeCoercion, TypeCoercionRewriter,
+    };
+    use crate::test::{assert_analyzed_plan_eq, assert_analyzed_plan_with_config_eq};
     use datafusion_common::config::ConfigOptions;
     use datafusion_common::tree_node::{TransformedResult, TreeNode};
     use datafusion_common::{DFSchema, DFSchemaRef, Result, ScalarValue};
@@ -1032,11 +1039,6 @@ mod test {
     };
     use datafusion_functions_aggregate::average::AvgAccumulator;
 
-    use crate::analyzer::type_coercion::{
-        coerce_case_expression, TypeCoercion, TypeCoercionRewriter,
-    };
-    use crate::test::{assert_analyzed_plan_eq, assert_analyzed_plan_with_config_eq};
-
     fn empty() -> Arc<LogicalPlan> {
         Arc::new(LogicalPlan::EmptyRelation(EmptyRelation {
             produce_one_row: false,

datafusion/optimizer/tests/optimizer_integration.rs

@@ -22,11 +22,13 @@ use std::sync::Arc;
 use arrow::datatypes::{DataType, Field, Schema, SchemaRef, TimeUnit};
 
 use datafusion_common::config::ConfigOptions;
-use datafusion_common::{plan_err, Result};
+use datafusion_common::{assert_contains, plan_err, Result};
+use datafusion_expr::sqlparser::dialect::PostgreSqlDialect;
 use datafusion_expr::test::function_stub::sum_udaf;
 use datafusion_expr::{AggregateUDF, LogicalPlan, ScalarUDF, TableSource, WindowUDF};
 use datafusion_functions_aggregate::average::avg_udaf;
 use datafusion_functions_aggregate::count::count_udaf;
+use datafusion_optimizer::analyzer::type_coercion::TypeCoercionRewriter;
 use datafusion_optimizer::analyzer::Analyzer;
 use datafusion_optimizer::optimizer::Optimizer;
 use datafusion_optimizer::{OptimizerConfig, OptimizerContext, OptimizerRule};
@@ -387,6 +389,32 @@ fn select_correlated_predicate_subquery_with_uppercase_ident() {
     assert_eq!(expected, format!("{plan}"));
 }
 
+// The test should return an error
+// because the wildcard didn't be expanded before type coercion
+#[test]
+fn test_union_coercion_with_wildcard() -> Result<()> {
+    let dialect = PostgreSqlDialect {};
+    let context_provider = MyContextProvider::default();
+    let sql = "select * from (SELECT col_int32, col_uint32 FROM test) union all select * from(SELECT col_uint32, col_int32 FROM test)";
+    let statements = Parser::parse_sql(&dialect, sql)?;
+    let sql_to_rel = SqlToRel::new(&context_provider);
+    let logical_plan = sql_to_rel.sql_statement_to_plan(statements[0].clone())?;
+
+    if let LogicalPlan::Union(union) = logical_plan {
+        let err = TypeCoercionRewriter::coerce_union(union)
+            .err()
+            .unwrap()
+            .to_string();
+        assert_contains!(
+            err,
+            "Error during planning: Wildcard should be expanded before type coercion"
+        );
+    } else {
+        panic!("Expected Union plan");
+    }
+    Ok(())
+}
+
 fn test_sql(sql: &str) -> Result<LogicalPlan> {
     // parse the SQL
     let dialect = GenericDialect {}; // or AnsiDialect, or your own dialect ...