1 files changed, 28 insertions, 0 deletions
diff --git a/src/test/regress/sql/join.sql b/src/test/regress/sql/join.sql
index bf18a8f6c42..af6d6129c8f 100644
--- a/src/test/regress/sql/join.sql
+++ b/src/test/regress/sql/join.sql
@@ -1730,3 +1730,31 @@ update xx1 set x2 = f1 from xx1, lateral (select * from int4_tbl where f1 = x1)
 delete from xx1 using (select * from int4_tbl where f1 = x1) ss;
 delete from xx1 using (select * from int4_tbl where f1 = xx1.x1) ss;
 delete from xx1 using lateral (select * from int4_tbl where f1 = x1) ss;
+
+--
+-- test that foreign key join estimation performs sanely for outer joins
+--
+
+begin;
+
+create table fkest (a int, b int, c int unique, primary key(a,b));
+create table fkest1 (a int, b int, primary key(a,b));
+
+insert into fkest select x/10, x%10, x from generate_series(1,1000) x;
+insert into fkest1 select x/10, x%10 from generate_series(1,1000) x;
+
+alter table fkest1
+  add constraint fkest1_a_b_fkey foreign key (a,b) references fkest;
+
+analyze fkest;
+analyze fkest1;
+
+explain (costs off)
+select *
+from fkest f
+  left join fkest1 f1 on f.a = f1.a and f.b = f1.b
+  left join fkest1 f2 on f.a = f2.a and f.b = f2.b
+  left join fkest1 f3 on f.a = f3.a and f.b = f3.b
+where f.c = 1;
+
+rollback;