diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 1db3bd9e2e..b3600b2dbd 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -15046,6 +15046,18 @@ MergeAttributesIntoExisting(Relation child_rel, Relation parent_rel)
 						 errmsg("column \"%s\" in child table must be a generated column",
 								attributeName)));
 
+			/*
+			 * Disallow partitions to have generated columns that are not in
+			 * the parent table too.
+			 */
+			if (child_is_partition &&
+				!attribute->attgenerated && childatt->attgenerated)
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("column \"%s\" is not a generated column in parent table",
+								attributeName),
+						 errdetail("Partitions cannot have generated columns that are not present in the parent table.")));
+
 			/*
 			 * Check that both generation expressions match.
 			 *
diff --git a/src/test/regress/expected/generated.out b/src/test/regress/expected/generated.out
index 1db5f9ed47..28f648bb5e 100644
--- a/src/test/regress/expected/generated.out
+++ b/src/test/regress/expected/generated.out
@@ -702,7 +702,11 @@ CREATE TABLE gtest_child PARTITION OF gtest_parent (
     f3 WITH OPTIONS GENERATED ALWAYS AS (f2 * 2) STORED
 ) FOR VALUES FROM ('2016-07-01') TO ('2016-08-01'); -- error
 ERROR:  generated columns are not supported on partitions
-DROP TABLE gtest_parent;
+CREATE TABLE gtest_child (f1 date NOT NULL, f2 text, f3 bigint GENERATED ALWAYS AS (2 * 2) STORED);
+ALTER TABLE gtest_parent ATTACH PARTITION gtest_child FOR VALUES FROM ('2016-07-01') TO ('2016-08-01'); -- error
+ERROR:  column "f3" is not a generated column in parent table
+DETAIL:  Partitions cannot have generated columns that are not present in the parent table.
+DROP TABLE gtest_parent, gtest_child;
 -- partitioned table
 CREATE TABLE gtest_parent (f1 date NOT NULL, f2 bigint, f3 bigint GENERATED ALWAYS AS (f2 * 2) STORED) PARTITION BY RANGE (f1);
 CREATE TABLE gtest_child PARTITION OF gtest_parent FOR VALUES FROM ('2016-07-01') TO ('2016-08-01');
diff --git a/src/test/regress/sql/generated.sql b/src/test/regress/sql/generated.sql
index 39eec40bce..2962181dc2 100644
--- a/src/test/regress/sql/generated.sql
+++ b/src/test/regress/sql/generated.sql
@@ -370,7 +370,9 @@ CREATE TABLE gtest_parent (f1 date NOT NULL, f2 text, f3 bigint) PARTITION BY RA
 CREATE TABLE gtest_child PARTITION OF gtest_parent (
     f3 WITH OPTIONS GENERATED ALWAYS AS (f2 * 2) STORED
 ) FOR VALUES FROM ('2016-07-01') TO ('2016-08-01'); -- error
-DROP TABLE gtest_parent;
+CREATE TABLE gtest_child (f1 date NOT NULL, f2 text, f3 bigint GENERATED ALWAYS AS (2 * 2) STORED);
+ALTER TABLE gtest_parent ATTACH PARTITION gtest_child FOR VALUES FROM ('2016-07-01') TO ('2016-08-01'); -- error
+DROP TABLE gtest_parent, gtest_child;
 
 -- partitioned table
 CREATE TABLE gtest_parent (f1 date NOT NULL, f2 bigint, f3 bigint GENERATED ALWAYS AS (f2 * 2) STORED) PARTITION BY RANGE (f1);