diff --git a/datafusion/core/tests/sql/subqueries.rs b/datafusion/core/tests/sql/subqueries.rs
index f91018d8bf645..97a63b3a95ab5 100644
--- a/datafusion/core/tests/sql/subqueries.rs
+++ b/datafusion/core/tests/sql/subqueries.rs
@@ -446,7 +446,7 @@ order by value desc;
   Projection: partsupp.ps_partkey, SUM(partsupp.ps_supplycost * partsupp.ps_availqty) AS value
     Filter: CAST(SUM(partsupp.ps_supplycost * partsupp.ps_availqty) AS Decimal128(38, 17)) > __sq_1.__value
       CrossJoin:
-        Aggregate: groupBy=[[partsupp.ps_partkey]], aggr=[[SUM(CAST(partsupp.ps_supplycost AS Decimal128(26, 2)) * CAST(partsupp.ps_availqty AS Decimal128(26, 2)))]]
+        Aggregate: groupBy=[[partsupp.ps_partkey]], aggr=[[SUM(CAST(partsupp.ps_supplycost AS Decimal128(26, 2)) * CAST(partsupp.ps_availqty AS Decimal128(26, 2))) AS SUM(partsupp.ps_supplycost * partsupp.ps_availqty)]]
           Inner Join: supplier.s_nationkey = nation.n_nationkey
             Inner Join: partsupp.ps_suppkey = supplier.s_suppkey
               TableScan: partsupp projection=[ps_partkey, ps_suppkey, ps_availqty, ps_supplycost]
@@ -454,7 +454,7 @@ order by value desc;
             Filter: nation.n_name = Utf8("GERMANY")
               TableScan: nation projection=[n_nationkey, n_name], partial_filters=[nation.n_name = Utf8("GERMANY")]
         Projection: CAST(SUM(partsupp.ps_supplycost * partsupp.ps_availqty) AS Decimal128(38, 17)) * CAST(Float64(0.0001) AS Decimal128(38, 17)) AS __value, alias=__sq_1
-          Aggregate: groupBy=[[]], aggr=[[SUM(CAST(partsupp.ps_supplycost AS Decimal128(26, 2)) * CAST(partsupp.ps_availqty AS Decimal128(26, 2)))]]
+          Aggregate: groupBy=[[]], aggr=[[SUM(CAST(partsupp.ps_supplycost AS Decimal128(26, 2)) * CAST(partsupp.ps_availqty AS Decimal128(26, 2))) AS SUM(partsupp.ps_supplycost * partsupp.ps_availqty)]]
             Inner Join: supplier.s_nationkey = nation.n_nationkey
               Inner Join: partsupp.ps_suppkey = supplier.s_suppkey
                 TableScan: partsupp projection=[ps_partkey, ps_suppkey, ps_availqty, ps_supplycost]
@@ -462,7 +462,7 @@ order by value desc;
               Filter: nation.n_name = Utf8("GERMANY")
                 TableScan: nation projection=[n_nationkey, n_name], partial_filters=[nation.n_name = Utf8("GERMANY")]"#
         .to_string();
-    assert_eq!(actual, expected);
+    assert_eq!(expected, actual);
 
     // assert data
     let results = execute_to_batches(&ctx, sql).await;
diff --git a/datafusion/optimizer/src/type_coercion.rs b/datafusion/optimizer/src/type_coercion.rs
index 2073713ddd312..7590803c36699 100644
--- a/datafusion/optimizer/src/type_coercion.rs
+++ b/datafusion/optimizer/src/type_coercion.rs
@@ -103,8 +103,8 @@ fn optimize_internal(
             // ensure aggregate names don't change:
             // https://github.com/apache/arrow-datafusion/issues/3555
             if matches!(expr, Expr::AggregateFunction { .. }) {
-                if let Some((alias, name)) = original_name.zip(expr.name().ok()) {
-                    if alias != name {
+                if let Some(alias) = original_name {
+                    if alias != expr.canonical_name() {
                         return Ok(expr.alias(&alias));
                     }
                 }
diff --git a/datafusion/optimizer/tests/integration-test.rs b/datafusion/optimizer/tests/integration-test.rs
index 6dea1a243ff2d..056c79b1669fb 100644
--- a/datafusion/optimizer/tests/integration-test.rs
+++ b/datafusion/optimizer/tests/integration-test.rs
@@ -46,6 +46,17 @@ fn case_when() -> Result<()> {
     Ok(())
 }
 
+#[test]
+fn case_when_aggregate() -> Result<()> {
+    let sql = "SELECT col_utf8, SUM(CASE WHEN col_int32 > 0 THEN 1 ELSE 0 END) AS n FROM test GROUP BY col_utf8";
+    let plan = test_sql(sql)?;
+    let expected = "Projection: test.col_utf8, SUM(CASE WHEN test.col_int32 > Int64(0) THEN Int64(1) ELSE Int64(0) END) AS n\
+    \n  Aggregate: groupBy=[[test.col_utf8]], aggr=[[SUM(CASE WHEN test.col_int32 > Int32(0) THEN Int64(1) ELSE Int64(0) END) AS SUM(CASE WHEN test.col_int32 > Int64(0) THEN Int64(1) ELSE Int64(0) END)]]\
+    \n    TableScan: test projection=[col_int32, col_utf8]";
+    assert_eq!(expected, format!("{:?}", plan));
+    Ok(())
+}
+
 #[test]
 fn unsigned_target_type() -> Result<()> {
     let sql = "SELECT * FROM test WHERE col_uint32 > 0";