diff --git a/sql/core/src/test/resources/sql-tests/inputs/udf/pgSQL/udf-select_implicit.sql b/sql/core/src/test/resources/sql-tests/inputs/udf/pgSQL/udf-select_implicit.sql
index 80edf12ef8ac..373896ccd167 100755
--- a/sql/core/src/test/resources/sql-tests/inputs/udf/pgSQL/udf-select_implicit.sql
+++ b/sql/core/src/test/resources/sql-tests/inputs/udf/pgSQL/udf-select_implicit.sql
@@ -10,8 +10,6 @@
 -- https://github.com/postgres/postgres/blob/REL_12_BETA2/src/test/regress/sql/select_implicit.sql
 --
 -- This test file was converted from pgSQL/select_implicit.sql
--- [SPARK-28445] Inconsistency between Scala and Python/Panda udfs when groupby with udf() is used
--- TODO: We should add UDFs in GROUP BY clause when [SPARK-28445] is resolved.
 
 -- load test data
 CREATE TABLE test_missing_target (a int, b int, c string, d string) using parquet;
@@ -29,29 +27,29 @@ INSERT INTO test_missing_target VALUES (9, 4, 'CCCC', 'j');
 
 --   w/ existing GROUP BY target
 SELECT udf(c), udf(count(*)) FROM test_missing_target GROUP BY
-test_missing_target.c
+udf(test_missing_target.c)
 ORDER BY udf(c);
 
 --   w/o existing GROUP BY target using a relation name in GROUP BY clause
-SELECT udf(count(*)) FROM test_missing_target GROUP BY test_missing_target.c
+SELECT udf(count(*)) FROM test_missing_target GROUP BY udf(test_missing_target.c)
 ORDER BY udf(c);
 
 --   w/o existing GROUP BY target and w/o existing a different ORDER BY target
 --   failure expected
-SELECT udf(count(*)) FROM test_missing_target GROUP BY a ORDER BY udf(b);
+SELECT udf(count(*)) FROM test_missing_target GROUP BY udf(a) ORDER BY udf(b);
 
 --   w/o existing GROUP BY target and w/o existing same ORDER BY target
-SELECT udf(count(*)) FROM test_missing_target GROUP BY b ORDER BY udf(b);
+SELECT udf(count(*)) FROM test_missing_target GROUP BY udf(b) ORDER BY udf(b);
 
 --   w/ existing GROUP BY target using a relation name in target
 SELECT udf(test_missing_target.b), udf(count(*))
-  FROM test_missing_target GROUP BY b ORDER BY udf(b);
+  FROM test_missing_target GROUP BY udf(b) ORDER BY udf(b);
 
 --   w/o existing GROUP BY target
 SELECT udf(c) FROM test_missing_target ORDER BY udf(a);
 
 --   w/o existing ORDER BY target
-SELECT udf(count(*)) FROM test_missing_target GROUP BY b ORDER BY udf(b) desc;
+SELECT udf(count(*)) FROM test_missing_target GROUP BY udf(b) ORDER BY udf(b) desc;
 
 --   group using reference number
 SELECT udf(count(*)) FROM test_missing_target ORDER BY udf(1) desc;
@@ -67,7 +65,7 @@ SELECT udf(c), udf(count(*)) FROM test_missing_target GROUP BY 3;
 --   failure expected
 SELECT udf(count(*)) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY b ORDER BY udf(b);
+	GROUP BY udf(b) ORDER BY udf(b);
 
 --   order w/ target under ambiguous condition
 --   failure NOT expected
@@ -82,17 +80,17 @@ SELECT udf(udf(a)/2), udf(udf(a)/2) FROM test_missing_target
 --   group expression w/ target under ambiguous condition
 --   failure NOT expected
 SELECT udf(a/2), udf(a/2) FROM test_missing_target
-	GROUP BY a/2 ORDER BY udf(a/2);
+	GROUP BY udf(a/2) ORDER BY udf(a/2);
 
 --   group w/ existing GROUP BY target under ambiguous condition
 SELECT udf(x.b), udf(count(*)) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY x.b ORDER BY udf(x.b);
+	GROUP BY udf(x.b) ORDER BY udf(x.b);
 
 --   group w/o existing GROUP BY target under ambiguous condition
 SELECT udf(count(*)) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY x.b ORDER BY udf(x.b);
+	GROUP BY udf(x.b) ORDER BY udf(x.b);
 
 -- [SPARK-28329] SELECT INTO syntax
 --   group w/o existing GROUP BY target under ambiguous condition
@@ -107,50 +105,50 @@ SELECT udf(count(*)) FROM test_missing_target x, test_missing_target y
 --  Functions and expressions
 
 --   w/ existing GROUP BY target
-SELECT a%2, udf(count(udf(b))) FROM test_missing_target
-GROUP BY test_missing_target.a%2
+SELECT udf(a%2), udf(count(udf(b))) FROM test_missing_target
+GROUP BY udf(test_missing_target.a%2)
 ORDER BY udf(test_missing_target.a%2);
 
 --   w/o existing GROUP BY target using a relation name in GROUP BY clause
 SELECT udf(count(c)) FROM test_missing_target
-GROUP BY lower(test_missing_target.c)
+GROUP BY udf(lower(test_missing_target.c))
 ORDER BY udf(lower(test_missing_target.c));
 
 --   w/o existing GROUP BY target and w/o existing a different ORDER BY target
 --   failure expected
-SELECT udf(count(udf(a))) FROM test_missing_target GROUP BY a ORDER BY udf(b);
+SELECT udf(count(udf(a))) FROM test_missing_target GROUP BY udf(a) ORDER BY udf(b);
 
 --   w/o existing GROUP BY target and w/o existing same ORDER BY target
-SELECT udf(count(b)) FROM test_missing_target GROUP BY b/2 ORDER BY udf(b/2);
+SELECT udf(count(b)) FROM test_missing_target GROUP BY udf(b/2) ORDER BY udf(b/2);
 
 --   w/ existing GROUP BY target using a relation name in target
 SELECT udf(lower(test_missing_target.c)), udf(count(udf(c)))
-  FROM test_missing_target GROUP BY lower(c) ORDER BY udf(lower(c));
+  FROM test_missing_target GROUP BY udf(lower(c)) ORDER BY udf(lower(c));
 
 --   w/o existing GROUP BY target
 SELECT udf(a) FROM test_missing_target ORDER BY udf(upper(udf(d)));
 
 --   w/o existing ORDER BY target
 SELECT udf(count(b)) FROM test_missing_target
-	GROUP BY (b + 1) / 2 ORDER BY udf((b + 1) / 2) desc;
+	GROUP BY udf((b + 1) / 2) ORDER BY udf((b + 1) / 2) desc;
 
 --   group w/o existing GROUP BY and ORDER BY target under ambiguous condition
 --   failure expected
 SELECT udf(count(udf(x.a))) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY b/2 ORDER BY udf(b/2);
+	GROUP BY udf(b/2) ORDER BY udf(b/2);
 
 --   group w/ existing GROUP BY target under ambiguous condition
 SELECT udf(x.b/2), udf(count(udf(x.b))) FROM test_missing_target x,
 test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY x.b/2 ORDER BY udf(x.b/2);
+	GROUP BY udf(x.b/2) ORDER BY udf(x.b/2);
 
 --   group w/o existing GROUP BY target under ambiguous condition
 --   failure expected due to ambiguous b in count(b)
 SELECT udf(count(udf(b))) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY x.b/2;
+	GROUP BY udf(x.b/2);
 
 -- [SPARK-28329] SELECT INTO syntax
 --   group w/o existing GROUP BY target under ambiguous condition
diff --git a/sql/core/src/test/resources/sql-tests/results/udf/pgSQL/udf-select_implicit.sql.out b/sql/core/src/test/resources/sql-tests/results/udf/pgSQL/udf-select_implicit.sql.out
index e6a5995d24d2..a60cbf33b9b2 100755
--- a/sql/core/src/test/resources/sql-tests/results/udf/pgSQL/udf-select_implicit.sql.out
+++ b/sql/core/src/test/resources/sql-tests/results/udf/pgSQL/udf-select_implicit.sql.out
@@ -92,7 +92,7 @@ struct<>
 
 -- !query 11
 SELECT udf(c), udf(count(*)) FROM test_missing_target GROUP BY
-test_missing_target.c
+udf(test_missing_target.c)
 ORDER BY udf(c)
 -- !query 11 schema
 struct<CAST(udf(cast(c as string)) AS STRING):string,CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
@@ -106,7 +106,7 @@ cccc	2
 
 
 -- !query 12
-SELECT udf(count(*)) FROM test_missing_target GROUP BY test_missing_target.c
+SELECT udf(count(*)) FROM test_missing_target GROUP BY udf(test_missing_target.c)
 ORDER BY udf(c)
 -- !query 12 schema
 struct<CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
@@ -120,16 +120,16 @@ struct<CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
 
 
 -- !query 13
-SELECT udf(count(*)) FROM test_missing_target GROUP BY a ORDER BY udf(b)
+SELECT udf(count(*)) FROM test_missing_target GROUP BY udf(a) ORDER BY udf(b)
 -- !query 13 schema
 struct<>
 -- !query 13 output
 org.apache.spark.sql.AnalysisException
-cannot resolve '`b`' given input columns: [CAST(udf(cast(count(1) as string)) AS BIGINT)]; line 1 pos 70
+cannot resolve '`b`' given input columns: [CAST(udf(cast(count(1) as string)) AS BIGINT)]; line 1 pos 75
 
 
 -- !query 14
-SELECT udf(count(*)) FROM test_missing_target GROUP BY b ORDER BY udf(b)
+SELECT udf(count(*)) FROM test_missing_target GROUP BY udf(b) ORDER BY udf(b)
 -- !query 14 schema
 struct<CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
 -- !query 14 output
@@ -141,7 +141,7 @@ struct<CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
 
 -- !query 15
 SELECT udf(test_missing_target.b), udf(count(*))
-  FROM test_missing_target GROUP BY b ORDER BY udf(b)
+  FROM test_missing_target GROUP BY udf(b) ORDER BY udf(b)
 -- !query 15 schema
 struct<CAST(udf(cast(b as string)) AS INT):int,CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
 -- !query 15 output
@@ -169,7 +169,7 @@ CCCC
 
 
 -- !query 17
-SELECT udf(count(*)) FROM test_missing_target GROUP BY b ORDER BY udf(b) desc
+SELECT udf(count(*)) FROM test_missing_target GROUP BY udf(b) ORDER BY udf(b) desc
 -- !query 17 schema
 struct<CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
 -- !query 17 output
@@ -212,12 +212,12 @@ GROUP BY position 3 is not in select list (valid range is [1, 2]); line 1 pos 63
 -- !query 21
 SELECT udf(count(*)) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY b ORDER BY udf(b)
+	GROUP BY udf(b) ORDER BY udf(b)
 -- !query 21 schema
 struct<>
 -- !query 21 output
 org.apache.spark.sql.AnalysisException
-Reference 'b' is ambiguous, could be: x.b, y.b.; line 3 pos 10
+Reference 'b' is ambiguous, could be: x.b, y.b.; line 3 pos 14
 
 
 -- !query 22
@@ -258,7 +258,7 @@ struct<CAST(udf(cast((cast(udf(cast(a as string)) as int) div 2) as string)) AS
 
 -- !query 24
 SELECT udf(a/2), udf(a/2) FROM test_missing_target
-	GROUP BY a/2 ORDER BY udf(a/2)
+	GROUP BY udf(a/2) ORDER BY udf(a/2)
 -- !query 24 schema
 struct<CAST(udf(cast((a div 2) as string)) AS INT):int,CAST(udf(cast((a div 2) as string)) AS INT):int>
 -- !query 24 output
@@ -272,7 +272,7 @@ struct<CAST(udf(cast((a div 2) as string)) AS INT):int,CAST(udf(cast((a div 2) a
 -- !query 25
 SELECT udf(x.b), udf(count(*)) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY x.b ORDER BY udf(x.b)
+	GROUP BY udf(x.b) ORDER BY udf(x.b)
 -- !query 25 schema
 struct<CAST(udf(cast(b as string)) AS INT):int,CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
 -- !query 25 output
@@ -285,7 +285,7 @@ struct<CAST(udf(cast(b as string)) AS INT):int,CAST(udf(cast(count(1) as string)
 -- !query 26
 SELECT udf(count(*)) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY x.b ORDER BY udf(x.b)
+	GROUP BY udf(x.b) ORDER BY udf(x.b)
 -- !query 26 schema
 struct<CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
 -- !query 26 output
@@ -296,11 +296,11 @@ struct<CAST(udf(cast(count(1) as string)) AS BIGINT):bigint>
 
 
 -- !query 27
-SELECT a%2, udf(count(udf(b))) FROM test_missing_target
-GROUP BY test_missing_target.a%2
+SELECT udf(a%2), udf(count(udf(b))) FROM test_missing_target
+GROUP BY udf(test_missing_target.a%2)
 ORDER BY udf(test_missing_target.a%2)
 -- !query 27 schema
-struct<(a % 2):int,CAST(udf(cast(count(cast(udf(cast(b as string)) as int)) as string)) AS BIGINT):bigint>
+struct<CAST(udf(cast((a % 2) as string)) AS INT):int,CAST(udf(cast(count(cast(udf(cast(b as string)) as int)) as string)) AS BIGINT):bigint>
 -- !query 27 output
 0	5
 1	5
@@ -308,7 +308,7 @@ struct<(a % 2):int,CAST(udf(cast(count(cast(udf(cast(b as string)) as int)) as s
 
 -- !query 28
 SELECT udf(count(c)) FROM test_missing_target
-GROUP BY lower(test_missing_target.c)
+GROUP BY udf(lower(test_missing_target.c))
 ORDER BY udf(lower(test_missing_target.c))
 -- !query 28 schema
 struct<CAST(udf(cast(count(c) as string)) AS BIGINT):bigint>
@@ -320,16 +320,16 @@ struct<CAST(udf(cast(count(c) as string)) AS BIGINT):bigint>
 
 
 -- !query 29
-SELECT udf(count(udf(a))) FROM test_missing_target GROUP BY a ORDER BY udf(b)
+SELECT udf(count(udf(a))) FROM test_missing_target GROUP BY udf(a) ORDER BY udf(b)
 -- !query 29 schema
 struct<>
 -- !query 29 output
 org.apache.spark.sql.AnalysisException
-cannot resolve '`b`' given input columns: [CAST(udf(cast(count(cast(udf(cast(a as string)) as int)) as string)) AS BIGINT)]; line 1 pos 75
+cannot resolve '`b`' given input columns: [CAST(udf(cast(count(cast(udf(cast(a as string)) as int)) as string)) AS BIGINT)]; line 1 pos 80
 
 
 -- !query 30
-SELECT udf(count(b)) FROM test_missing_target GROUP BY b/2 ORDER BY udf(b/2)
+SELECT udf(count(b)) FROM test_missing_target GROUP BY udf(b/2) ORDER BY udf(b/2)
 -- !query 30 schema
 struct<CAST(udf(cast(count(b) as string)) AS BIGINT):bigint>
 -- !query 30 output
@@ -340,7 +340,7 @@ struct<CAST(udf(cast(count(b) as string)) AS BIGINT):bigint>
 
 -- !query 31
 SELECT udf(lower(test_missing_target.c)), udf(count(udf(c)))
-  FROM test_missing_target GROUP BY lower(c) ORDER BY udf(lower(c))
+  FROM test_missing_target GROUP BY udf(lower(c)) ORDER BY udf(lower(c))
 -- !query 31 schema
 struct<CAST(udf(cast(lower(c) as string)) AS STRING):string,CAST(udf(cast(count(cast(udf(cast(c as string)) as string)) as string)) AS BIGINT):bigint>
 -- !query 31 output
@@ -369,7 +369,7 @@ struct<CAST(udf(cast(a as string)) AS INT):int>
 
 -- !query 33
 SELECT udf(count(b)) FROM test_missing_target
-	GROUP BY (b + 1) / 2 ORDER BY udf((b + 1) / 2) desc
+	GROUP BY udf((b + 1) / 2) ORDER BY udf((b + 1) / 2) desc
 -- !query 33 schema
 struct<CAST(udf(cast(count(b) as string)) AS BIGINT):bigint>
 -- !query 33 output
@@ -380,19 +380,19 @@ struct<CAST(udf(cast(count(b) as string)) AS BIGINT):bigint>
 -- !query 34
 SELECT udf(count(udf(x.a))) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY b/2 ORDER BY udf(b/2)
+	GROUP BY udf(b/2) ORDER BY udf(b/2)
 -- !query 34 schema
 struct<>
 -- !query 34 output
 org.apache.spark.sql.AnalysisException
-Reference 'b' is ambiguous, could be: x.b, y.b.; line 3 pos 10
+Reference 'b' is ambiguous, could be: x.b, y.b.; line 3 pos 14
 
 
 -- !query 35
 SELECT udf(x.b/2), udf(count(udf(x.b))) FROM test_missing_target x,
 test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY x.b/2 ORDER BY udf(x.b/2)
+	GROUP BY udf(x.b/2) ORDER BY udf(x.b/2)
 -- !query 35 schema
 struct<CAST(udf(cast((b div 2) as string)) AS INT):int,CAST(udf(cast(count(cast(udf(cast(b as string)) as int)) as string)) AS BIGINT):bigint>
 -- !query 35 output
@@ -404,7 +404,7 @@ struct<CAST(udf(cast((b div 2) as string)) AS INT):int,CAST(udf(cast(count(cast(
 -- !query 36
 SELECT udf(count(udf(b))) FROM test_missing_target x, test_missing_target y
 	WHERE udf(x.a) = udf(y.a)
-	GROUP BY x.b/2
+	GROUP BY udf(x.b/2)
 -- !query 36 schema
 struct<>
 -- !query 36 output