diff --git a/doc/src/sgml/ref/alter_foreign_table.sgml b/doc/src/sgml/ref/alter_foreign_table.sgml
index 5d373ae9a34..9f1a63fc96e 100644
--- a/doc/src/sgml/ref/alter_foreign_table.sgml
+++ b/doc/src/sgml/ref/alter_foreign_table.sgml
@@ -32,7 +32,7 @@ ALTER FOREIGN TABLE [ IF EXISTS ] <replaceable class="parameter">name</replaceab
 
 <phrase>where <replaceable class="parameter">action</replaceable> is one of:</phrase>
 
-    ADD [ COLUMN ] <replaceable class="parameter">column_name</replaceable> <replaceable class="parameter">data_type</replaceable> [ COLLATE <replaceable class="parameter">collation</replaceable> ] [ <replaceable class="parameter">column_constraint</replaceable> [ ... ] ]
+    ADD [ COLUMN ] [ IF NOT EXISTS ] <replaceable class="parameter">column_name</replaceable> <replaceable class="parameter">data_type</replaceable> [ COLLATE <replaceable class="parameter">collation</replaceable> ] [ <replaceable class="parameter">column_constraint</replaceable> [ ... ] ]
     DROP [ COLUMN ] [ IF EXISTS ] <replaceable class="parameter">column_name</replaceable> [ RESTRICT | CASCADE ]
     ALTER [ COLUMN ] <replaceable class="parameter">column_name</replaceable> [ SET DATA ] TYPE <replaceable class="parameter">data_type</replaceable> [ COLLATE <replaceable class="parameter">collation</replaceable> ]
     ALTER [ COLUMN ] <replaceable class="parameter">column_name</replaceable> SET DEFAULT <replaceable class="parameter">expression</replaceable>
@@ -67,11 +67,13 @@ ALTER FOREIGN TABLE [ IF EXISTS ] <replaceable class="parameter">name</replaceab
 
   <variablelist>
    <varlistentry>
-    <term><literal>ADD COLUMN</literal></term>
+    <term><literal>ADD [ COLUMN ] [ IF NOT EXISTS ]</literal></term>
     <listitem>
      <para>
       This form adds a new column to the foreign table, using the same syntax as
       <link linkend="sql-createforeigntable"><command>CREATE FOREIGN TABLE</command></link>.
+      If <literal>IF NOT EXISTS</literal> is specified and a column already
+      exists with this name, no error is thrown.
       Unlike the case when adding a column to a regular table, nothing happens
       to the underlying storage: this action simply declares that
       some new column is now accessible through the foreign table.
@@ -80,7 +82,7 @@ ALTER FOREIGN TABLE [ IF EXISTS ] <replaceable class="parameter">name</replaceab
    </varlistentry>
 
    <varlistentry>
-    <term><literal>DROP COLUMN [ IF EXISTS ]</literal></term>
+    <term><literal>DROP [ COLUMN ] [ IF EXISTS ]</literal></term>
     <listitem>
      <para>
       This form drops a column from a foreign table.
diff --git a/src/test/regress/expected/foreign_data.out b/src/test/regress/expected/foreign_data.out
index 25e71631a72..831efa4057f 100644
--- a/src/test/regress/expected/foreign_data.out
+++ b/src/test/regress/expected/foreign_data.out
@@ -828,10 +828,13 @@ COMMENT ON COLUMN ft1.c1 IS NULL;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c4 integer;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c5 integer DEFAULT 0;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c6 integer;
+ALTER FOREIGN TABLE ft1 ADD COLUMN IF NOT EXISTS c6 integer;
+NOTICE:  column "c6" of relation "ft1" already exists, skipping
 ALTER FOREIGN TABLE ft1 ADD COLUMN c7 integer NOT NULL;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c8 integer;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c9 integer;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c10 integer OPTIONS (p1 'v1');
+ALTER FOREIGN TABLE ft1 ADD c11 integer;
 ALTER FOREIGN TABLE ft1 ALTER COLUMN c4 SET DEFAULT 0;
 ALTER FOREIGN TABLE ft1 ALTER COLUMN c5 DROP DEFAULT;
 ALTER FOREIGN TABLE ft1 ALTER COLUMN c6 SET NOT NULL;
@@ -863,6 +866,7 @@ ALTER FOREIGN TABLE ft1 ALTER COLUMN c8 SET STORAGE PLAIN;
  c8     | text    |           |          |         | (p2 'V2')                      | plain    |              | 
  c9     | integer |           |          |         |                                | plain    |              | 
  c10    | integer |           |          |         | (p1 'v1')                      | plain    |              | 
+ c11    | integer |           |          |         |                                | plain    |              | 
 Check constraints:
     "ft1_c2_check" CHECK (c2 <> ''::text)
     "ft1_c3_check" CHECK (c3 >= '01-01-1994'::date AND c3 <= '01-31-1994'::date)
@@ -894,6 +898,7 @@ ERROR:  column "no_column" of relation "ft1" does not exist
 ALTER FOREIGN TABLE ft1 DROP COLUMN IF EXISTS no_column;
 NOTICE:  column "no_column" of relation "ft1" does not exist, skipping
 ALTER FOREIGN TABLE ft1 DROP COLUMN c9;
+ALTER FOREIGN TABLE ft1 DROP c11;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c11 serial;
 ALTER FOREIGN TABLE ft1 SET SCHEMA foreign_schema;
 ALTER FOREIGN TABLE ft1 SET TABLESPACE ts;                      -- ERROR
@@ -928,6 +933,8 @@ ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c4 integer;
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c6 integer;
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
+ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN IF NOT EXISTS c6 integer;
+NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c7 integer NOT NULL;
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c8 integer;
@@ -936,6 +943,8 @@ ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c9 integer;
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c10 integer OPTIONS (p1 'v1');
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
+ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD c11 integer;
+NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ALTER COLUMN c6 SET NOT NULL;
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ALTER COLUMN c7 DROP NOT NULL;
@@ -957,10 +966,14 @@ ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 OWNER TO regress_test_role;
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 OPTIONS (DROP delimiter, SET quote '~', ADD escape '@');
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
+ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP COLUMN no_column;
+NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP COLUMN IF EXISTS no_column;
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP COLUMN c9;
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
+ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP c11;
+NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 SET SCHEMA foreign_schema;
 NOTICE:  relation "doesnt_exist_ft1" does not exist, skipping
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 RENAME c1 TO foreign_column_1;
diff --git a/src/test/regress/sql/foreign_data.sql b/src/test/regress/sql/foreign_data.sql
index aa147b14a90..084d5559e09 100644
--- a/src/test/regress/sql/foreign_data.sql
+++ b/src/test/regress/sql/foreign_data.sql
@@ -383,10 +383,12 @@ COMMENT ON COLUMN ft1.c1 IS NULL;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c4 integer;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c5 integer DEFAULT 0;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c6 integer;
+ALTER FOREIGN TABLE ft1 ADD COLUMN IF NOT EXISTS c6 integer;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c7 integer NOT NULL;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c8 integer;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c9 integer;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c10 integer OPTIONS (p1 'v1');
+ALTER FOREIGN TABLE ft1 ADD c11 integer;
 
 ALTER FOREIGN TABLE ft1 ALTER COLUMN c4 SET DEFAULT 0;
 ALTER FOREIGN TABLE ft1 ALTER COLUMN c5 DROP DEFAULT;
@@ -419,6 +421,7 @@ ALTER FOREIGN TABLE ft1 OPTIONS (DROP delimiter, SET quote '~', ADD escape '@');
 ALTER FOREIGN TABLE ft1 DROP COLUMN no_column;                  -- ERROR
 ALTER FOREIGN TABLE ft1 DROP COLUMN IF EXISTS no_column;
 ALTER FOREIGN TABLE ft1 DROP COLUMN c9;
+ALTER FOREIGN TABLE ft1 DROP c11;
 ALTER FOREIGN TABLE ft1 ADD COLUMN c11 serial;
 ALTER FOREIGN TABLE ft1 SET SCHEMA foreign_schema;
 ALTER FOREIGN TABLE ft1 SET TABLESPACE ts;                      -- ERROR
@@ -430,10 +433,12 @@ ALTER FOREIGN TABLE foreign_schema.ft1 RENAME TO foreign_table_1;
 -- alter noexisting table
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c4 integer;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c6 integer;
+ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN IF NOT EXISTS c6 integer;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c7 integer NOT NULL;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c8 integer;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c9 integer;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD COLUMN c10 integer OPTIONS (p1 'v1');
+ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ADD c11 integer;
 
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ALTER COLUMN c6 SET NOT NULL;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 ALTER COLUMN c7 DROP NOT NULL;
@@ -447,8 +452,10 @@ ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP CONSTRAINT IF EXISTS no_cons
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP CONSTRAINT ft1_c1_check;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 OWNER TO regress_test_role;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 OPTIONS (DROP delimiter, SET quote '~', ADD escape '@');
+ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP COLUMN no_column;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP COLUMN IF EXISTS no_column;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP COLUMN c9;
+ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 DROP c11;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 SET SCHEMA foreign_schema;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 RENAME c1 TO foreign_column_1;
 ALTER FOREIGN TABLE IF EXISTS doesnt_exist_ft1 RENAME TO foreign_table_1;