Merging upstream version 18.3.0.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 13 insertions, 2 deletions

diff --git a/tests/dialects/test_postgres.py b/tests/dialects/test_postgres.py
index 8740aca..21196b7 100644
--- a/tests/dialects/test_postgres.py
+++ b/tests/dialects/test_postgres.py
@@ -126,12 +126,17 @@ class TestPostgres(Validator):
         )
 
     def test_postgres(self):
-        self.validate_identity("x @@ y")
-
         expr = parse_one("SELECT * FROM r CROSS JOIN LATERAL UNNEST(ARRAY[1]) AS s(location)")
         unnest = expr.args["joins"][0].this.this
         unnest.assert_is(exp.Unnest)
 
+        alter_table_only = """ALTER TABLE ONLY "Album" ADD CONSTRAINT "FK_AlbumArtistId" FOREIGN KEY ("ArtistId") REFERENCES "Artist" ("ArtistId") ON DELETE NO ACTION ON UPDATE NO ACTION"""
+        expr = parse_one(alter_table_only)
+
+        self.assertIsInstance(expr, exp.AlterTable)
+        self.assertEqual(expr.sql(dialect="postgres"), alter_table_only)
+
+        self.validate_identity("x @@ y")
         self.validate_identity("CAST(x AS MONEY)")
         self.validate_identity("CAST(x AS INT4RANGE)")
         self.validate_identity("CAST(x AS INT4MULTIRANGE)")
@@ -619,6 +624,12 @@ class TestPostgres(Validator):
                 "snowflake": "MERGE INTO x USING (SELECT id) AS y ON a = b WHEN MATCHED THEN UPDATE SET x.a = y.b",
             },
         )
+        self.validate_all(
+            "MERGE INTO x USING (SELECT id) AS y ON a = b WHEN MATCHED THEN UPDATE SET x.a = y.b WHEN NOT MATCHED THEN INSERT (a, b) VALUES (y.a, y.b)",
+            write={
+                "postgres": "MERGE INTO x USING (SELECT id) AS y ON a = b WHEN MATCHED THEN UPDATE SET a = y.b WHEN NOT MATCHED THEN INSERT (a, b) VALUES (y.a, y.b)",
+            },
+        )
 
         self.validate_all(
             "x / y ^ z",