Add test cases for materialize view

tests/test_materialize.py

@@ -0,0 +1,93 @@
+#!/usr/bin/env python3
+
+import unittest
+from chdb import session
+
+
+class TestMaterialize(unittest.TestCase):
+    def test_materialize(self):
+        sess = session.Session()
+
+        ret = sess.query("CREATE DATABASE IF NOT EXISTS db_xxx ENGINE = Atomic")
+        self.assertFalse(ret.has_error())
+        ret = sess.query("USE db_xxx")
+        self.assertFalse(ret.has_error())
+        ret = sess.query(
+            """
+        CREATE TABLE download (
+        when DateTime,
+        userid UInt32,
+        bytes Float32
+        ) ENGINE=MergeTree
+        PARTITION BY toYYYYMM(when)
+        ORDER BY (userid, when)"""
+        )
+        self.assertFalse(ret.has_error())
+        sess.query(
+            """
+        INSERT INTO download
+        SELECT
+            now() + number * 60 as when,
+            25,
+            rand() % 100000000
+        FROM system.numbers
+        LIMIT 5000"""
+        )
+        ret = sess.query(
+            """
+        SELECT
+        toStartOfDay(when) AS day,
+        userid,
+        count() as downloads,
+        sum(bytes) AS bytes
+        FROM download
+        GROUP BY userid, day
+        ORDER BY userid, day"""
+        )
+        print("Result from agg:", ret)
+
+        sess.query(
+            """CREATE MATERIALIZED VIEW download_daily_mv
+        ENGINE = SummingMergeTree
+        PARTITION BY toYYYYMM(day) ORDER BY (userid, day)
+        POPULATE
+        AS SELECT
+        toStartOfDay(when) AS day,
+        userid,
+        count() as downloads,
+        sum(bytes) AS bytes
+        FROM download
+        GROUP BY userid, day"""
+        )
+        ret1 = sess.query(
+            """SELECT * FROM download_daily_mv
+        ORDER BY day, userid 
+        LIMIT 5"""
+        )
+        print("Result from mv:", ret1)
+        print("Show result:")
+        ret1.show()
+        self.assertEqual(str(ret), str(ret1))
+
+        sess.query(
+            """
+        INSERT INTO download
+                SELECT
+            now() + number * 60 as when,
+            25,
+            rand() % 100000000
+        FROM system.numbers
+        LIMIT 5000"""
+        )
+        ret2 = sess.query(
+            """SELECT * FROM download_daily_mv
+        ORDER BY day, userid
+        LIMIT 5"""
+        )
+        print("Result from mv after insert:", ret2)
+
+        self.assertNotEqual(str(ret1), str(ret2))
+
+
+if __name__ == "__main__":
+    unittest.main()