diff --git a/src/test/regress/expected/planner_est.out b/src/test/regress/expected/planner_est.out
index b62a47552fa..3ef720908f5 100644
--- a/src/test/regress/expected/planner_est.out
+++ b/src/test/regress/expected/planner_est.out
@@ -210,4 +210,213 @@ false, true, false, true);
      ->  Result  (cost=N..N rows=1 width=N)
 (4 rows)
 
+-- Ensure stable and rich MCV statistics
+SET default_statistics_target = 1000;
+CREATE TABLE t_mcv (a int);
+-- Build ~100 MCV values with uniform distribution
+INSERT INTO t_mcv
+SELECT (i % 100)
+FROM generate_series(1, 20000) s(i);
+ANALYZE t_mcv;
+-- =========================================================
+-- CASE 1: Large ANY list (MCV < ANY) → hash on MCV
+-- =========================================================
+-- 1. Single element
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY(SELECT 1));$$,
+false, true, false, true);
+                explain_mask_costs                
+--------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=1912 width=N)
+   Filter: (a = ANY ((InitPlan array_1).col1))
+   InitPlan array_1
+     ->  Result  (cost=N..N rows=1 width=N)
+(4 rows)
+
+-- 2. Multiple elements (all in MCV)
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY(SELECT i FROM generate_series(1,3) s(i)));$$,
+false, true, false, true);
+                           explain_mask_costs                           
+------------------------------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=1912 width=N)
+   Filter: (a = ANY ((InitPlan array_1).col1))
+   InitPlan array_1
+     ->  Function Scan on generate_series s  (cost=N..N rows=3 width=N)
+(4 rows)
+
+-- 3. Includes non-MCV values
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[1, 2, 1000]);$$,
+false, true, false, true);
+               explain_mask_costs                
+-------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=400 width=N)
+   Filter: (a = ANY ('{1,2,1000}'::integer[]))
+(2 rows)
+
+-- 4. Duplicates
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY(SELECT (i % 3) + 1 FROM generate_series(1,30) s(i)));$$,
+false, true, false, true);
+                           explain_mask_costs                            
+-------------------------------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=1912 width=N)
+   Filter: (a = ANY ((InitPlan array_1).col1))
+   InitPlan array_1
+     ->  Function Scan on generate_series s  (cost=N..N rows=30 width=N)
+(4 rows)
+
+-- =========================================================
+-- CASE 2: Small ANY list (ANY < MCV) → hash on ANY
+-- =========================================================
+-- 1. Single element
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[10]);$$,
+false, true, false, true);
+               explain_mask_costs                
+-------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=200 width=N)
+   Filter: (a = ANY ('{10}'::integer[]))
+(2 rows)
+
+-- 2. Multiple elements (all in MCV)
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[10,20,30]);$$,
+false, true, false, true);
+               explain_mask_costs                
+-------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=600 width=N)
+   Filter: (a = ANY ('{10,20,30}'::integer[]))
+(2 rows)
+
+-- 3. Includes non-MCV values
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[10,20,10000]);$$,
+false, true, false, true);
+                explain_mask_costs                
+--------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=400 width=N)
+   Filter: (a = ANY ('{10,20,10000}'::integer[]))
+(2 rows)
+
+-- 4. Duplicates
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[10,10,10,20,20]);$$,
+false, true, false, true);
+                 explain_mask_costs                  
+-----------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=1000 width=N)
+   Filter: (a = ANY ('{10,10,10,20,20}'::integer[]))
+(2 rows)
+
+-- =========================================================
+-- CASE 3: Guaranteed large case → stress hash path
+-- =========================================================
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY(SELECT i % 100 FROM generate_series(1,500) s(i)));$$,
+false, true, false, true);
+                            explain_mask_costs                            
+--------------------------------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=1912 width=N)
+   Filter: (a = ANY ((InitPlan array_1).col1))
+   InitPlan array_1
+     ->  Function Scan on generate_series s  (cost=N..N rows=500 width=N)
+(4 rows)
+
+-- =========================================================
+-- CASE 4: inequality (<> ALL)
+-- =========================================================
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a <> ALL (ARRAY[1,2,3]);$$,
+false, true, false, true);
+                explain_mask_costs                 
+---------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=19400 width=N)
+   Filter: (a <> ALL ('{1,2,3}'::integer[]))
+(2 rows)
+
+-- =========================================================
+-- CASE 5: mix const + non-const
+-- =========================================================
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[1,2] || ARRAY(SELECT i FROM generate_series(3,5) s(i)));$$,
+false, true, false, true);
+                           explain_mask_costs                           
+------------------------------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=1912 width=N)
+   Filter: (a = ANY (('{1,2}'::integer[] || (InitPlan array_1).col1)))
+   InitPlan array_1
+     ->  Function Scan on generate_series s  (cost=N..N rows=3 width=N)
+(4 rows)
+
+-- =========================================================
+-- CASE 6: NULL handling
+-- =========================================================
+-- ANY with NULL
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[NULL,1]);$$,
+false, true, false, true);
+               explain_mask_costs                
+-------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=200 width=N)
+   Filter: (a = ANY ('{NULL,1}'::integer[]))
+(2 rows)
+
+-- ALL with NULL (should be 0 selectivity)
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ALL (ARRAY[1,NULL]);$$,
+false, true, false, true);
+              explain_mask_costs               
+-----------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=1 width=N)
+   Filter: (a = ALL ('{1,NULL}'::integer[]))
+(2 rows)
+
+-- =========================================================
+-- CASE 7: Combined all of them
+-- =========================================================
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[1, 2, 3, 1000, 2000, NULL, 1, 1, 2, (SELECT 4), (SELECT 5), (SELECT 10000), (SELECT 4), (SELECT 4)] || ARRAY( SELECT i % 120 FROM generate_series(1, 500) s(i)));$$,
+false, true, false, true);
+                                                                                                      explain_mask_costs                                                                                                       
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=1912 width=N)
+   Filter: (a = ANY ((ARRAY[1, 2, 3, 1000, 2000, NULL::integer, 1, 1, 2, (InitPlan expr_1).col1, (InitPlan expr_2).col1, (InitPlan expr_3).col1, (InitPlan expr_4).col1, (InitPlan expr_5).col1] || (InitPlan array_1).col1)))
+   InitPlan expr_1
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan expr_2
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan expr_3
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan expr_4
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan expr_5
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan array_1
+     ->  Function Scan on generate_series s  (cost=N..N rows=500 width=N)
+(14 rows)
+
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a <> ALL (ARRAY[1, 2, 3, 1000, 2000, NULL, 1, 1, 2, (SELECT 4), (SELECT 5), (SELECT 10000), (SELECT 4), (SELECT 4)] || ARRAY( SELECT i % 120 FROM generate_series(1, 500) s(i)));$$,
+false, true, false, true);
+                                                                                                       explain_mask_costs                                                                                                       
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ Seq Scan on t_mcv  (cost=N..N rows=18088 width=N)
+   Filter: (a <> ALL ((ARRAY[1, 2, 3, 1000, 2000, NULL::integer, 1, 1, 2, (InitPlan expr_1).col1, (InitPlan expr_2).col1, (InitPlan expr_3).col1, (InitPlan expr_4).col1, (InitPlan expr_5).col1] || (InitPlan array_1).col1)))
+   InitPlan expr_1
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan expr_2
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan expr_3
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan expr_4
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan expr_5
+     ->  Result  (cost=N..N rows=1 width=N)
+   InitPlan array_1
+     ->  Function Scan on generate_series s  (cost=N..N rows=500 width=N)
+(14 rows)
+
+DROP TABLE t_mcv;
 DROP FUNCTION explain_mask_costs(text, bool, bool, bool, bool);
diff --git a/src/test/regress/sql/planner_est.sql b/src/test/regress/sql/planner_est.sql
index 53210d5baad..ba8f8bd8fb6 100644
--- a/src/test/regress/sql/planner_est.sql
+++ b/src/test/regress/sql/planner_est.sql
@@ -147,4 +147,116 @@ SELECT explain_mask_costs($$
 SELECT * FROM tenk1 WHERE unique1 <> ALL (ARRAY[1, 2, 98, (SELECT 99), NULL]);$$,
 false, true, false, true);
 
+-- Ensure stable and rich MCV statistics
+SET default_statistics_target = 1000;
+
+CREATE TABLE t_mcv (a int);
+
+-- Build ~100 MCV values with uniform distribution
+INSERT INTO t_mcv
+SELECT (i % 100)
+FROM generate_series(1, 20000) s(i);
+
+ANALYZE t_mcv;
+
+-- =========================================================
+-- CASE 1: Large ANY list (MCV < ANY) → hash on MCV
+-- =========================================================
+
+-- 1. Single element
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY(SELECT 1));$$,
+false, true, false, true);
+
+-- 2. Multiple elements (all in MCV)
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY(SELECT i FROM generate_series(1,3) s(i)));$$,
+false, true, false, true);
+
+-- 3. Includes non-MCV values
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[1, 2, 1000]);$$,
+false, true, false, true);
+
+-- 4. Duplicates
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY(SELECT (i % 3) + 1 FROM generate_series(1,30) s(i)));$$,
+false, true, false, true);
+
+-- =========================================================
+-- CASE 2: Small ANY list (ANY < MCV) → hash on ANY
+-- =========================================================
+
+-- 1. Single element
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[10]);$$,
+false, true, false, true);
+
+-- 2. Multiple elements (all in MCV)
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[10,20,30]);$$,
+false, true, false, true);
+
+-- 3. Includes non-MCV values
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[10,20,10000]);$$,
+false, true, false, true);
+
+-- 4. Duplicates
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[10,10,10,20,20]);$$,
+false, true, false, true);
+
+-- =========================================================
+-- CASE 3: Guaranteed large case → stress hash path
+-- =========================================================
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY(SELECT i % 100 FROM generate_series(1,500) s(i)));$$,
+false, true, false, true);
+
+-- =========================================================
+-- CASE 4: inequality (<> ALL)
+-- =========================================================
+
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a <> ALL (ARRAY[1,2,3]);$$,
+false, true, false, true);
+
+-- =========================================================
+-- CASE 5: mix const + non-const
+-- =========================================================
+
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[1,2] || ARRAY(SELECT i FROM generate_series(3,5) s(i)));$$,
+false, true, false, true);
+
+-- =========================================================
+-- CASE 6: NULL handling
+-- =========================================================
+
+-- ANY with NULL
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[NULL,1]);$$,
+false, true, false, true);
+
+-- ALL with NULL (should be 0 selectivity)
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ALL (ARRAY[1,NULL]);$$,
+false, true, false, true);
+
+-- =========================================================
+-- CASE 7: Combined all of them
+-- =========================================================
+
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a = ANY (ARRAY[1, 2, 3, 1000, 2000, NULL, 1, 1, 2, (SELECT 4), (SELECT 5), (SELECT 10000), (SELECT 4), (SELECT 4)] || ARRAY( SELECT i % 120 FROM generate_series(1, 500) s(i)));$$,
+false, true, false, true);
+
+SELECT explain_mask_costs($$
+SELECT * FROM t_mcv WHERE a <> ALL (ARRAY[1, 2, 3, 1000, 2000, NULL, 1, 1, 2, (SELECT 4), (SELECT 5), (SELECT 10000), (SELECT 4), (SELECT 4)] || ARRAY( SELECT i % 120 FROM generate_series(1, 500) s(i)));$$,
+false, true, false, true);
+
+DROP TABLE t_mcv;
+
+
 DROP FUNCTION explain_mask_costs(text, bool, bool, bool, bool);