diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 5528749b953..7a0c8d9e033 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -1050,6 +1050,17 @@ drop table atacc1;
 create table atacc1 (id int not null);
 alter table atacc1 drop column id, add column id int, add primary key (id);
 drop table atacc1;
+-- Likewise when an earlier subcommand drops the not-null constraint itself.
+create table atacc1 (id int not null);
+alter table atacc1 alter column id drop not null, add primary key (id);
+drop table atacc1;
+create table atacc1 (id int constraint atacc1_id_nn not null);
+alter table atacc1 drop constraint atacc1_id_nn, add primary key (id);
+drop table atacc1;
+create table atacc1 (id int not null) partition by range (id);
+create table atacc1_1 partition of atacc1 for values from (0) to (10);
+alter table atacc1 alter column id drop not null, add primary key (id);
+drop table atacc1;
 -- this combination used to have order-of-execution problems (bug #15580)
 create table atacc1 (a int);
 insert into atacc1 values(1);
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index 6e28b5539eb..0d4ba7dad26 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -786,6 +786,17 @@ drop table atacc1;
 create table atacc1 (id int not null);
 alter table atacc1 drop column id, add column id int, add primary key (id);
 drop table atacc1;
+-- Likewise when an earlier subcommand drops the not-null constraint itself.
+create table atacc1 (id int not null);
+alter table atacc1 alter column id drop not null, add primary key (id);
+drop table atacc1;
+create table atacc1 (id int constraint atacc1_id_nn not null);
+alter table atacc1 drop constraint atacc1_id_nn, add primary key (id);
+drop table atacc1;
+create table atacc1 (id int not null) partition by range (id);
+create table atacc1_1 partition of atacc1 for values from (0) to (10);
+alter table atacc1 alter column id drop not null, add primary key (id);
+drop table atacc1;
 
 -- this combination used to have order-of-execution problems (bug #15580)
 create table atacc1 (a int);