should be it

external/duckdb/test/sql/upsert/minimal_reproducable_example.test

@@ -0,0 +1,34 @@
+# name: test/sql/upsert/minimal_reproducable_example.test
+# group: [upsert]
+
+statement ok
+pragma enable_verification;
+
+# Create a table with 3 columns, 2 of which are indexed on
+statement ok
+create or replace table tbl(
+	i integer PRIMARY KEY,
+	j integer UNIQUE,
+	k integer
+);
+
+# Add 3 rows
+statement ok
+insert into tbl VALUES (1, 10, 1), (2, 20, 1), (3, 30, 2);
+
+query III
+select * from tbl;
+----
+1	10	1
+2	20	1
+3	30	2
+
+statement ok
+insert into tbl VALUES (3,5,1) ON CONFLICT (i) DO UPDATE SET k = k + excluded.k;
+
+query III
+select * from tbl;
+----
+1	10	1
+2	20	1
+3	30	3