bug: drop bug fix (#1165)

Cannot reproduce the bug but added robust testcases. 

#1149 The inconsistent behavior might be happening because of another
bug where we were creating a table even if the select query failed. We
have fixed that, so it may fix this bug as well.

test/integration_tests/long/test_create_table_executor.py

@@ -82,6 +82,11 @@ def test_should_create_table_from_select(self):
         expected_batch = Batch(frames=pd.DataFrame(expected))
         self.assertEqual(actual_batch, expected_batch)
 
+        execute_query_fetch_all(self.evadb, "DROP TABLE IF EXISTS dummy_table;")
+
+        # re create table should work
+        execute_query_fetch_all(self.evadb, create_query)
+
     @macos_skip_marker
     @pytest.mark.torchtest
     def test_should_create_table_from_select_lateral_join(self):
@@ -102,6 +107,12 @@ def test_should_create_table_from_select_lateral_join(self):
         for idx in res.index:
             self.assertTrue("car" in res["uadtrac_fastrcnn.label"][idx])
 
+        execute_query_fetch_all(self.evadb, "DROP TABLE IF EXISTS uadtrac_fastRCNN;")
+
+        # re create table should work
+        query = "CREATE TABLE IF NOT EXISTS " f"uadtrac_fastRCNN AS {select_query};"
+        execute_query_fetch_all(self.evadb, query)
+
 
 if __name__ == "__main__":
     unittest.main()

test/integration_tests/short/test_drop_executor.py

@@ -112,6 +112,11 @@ def test_should_drop_table(self):
                 self.evadb, drop_query, do_not_print_exceptions=True
             )
 
+        # we should be able to re-create the table
+        execute_query_fetch_all(self.evadb, query)
+        # clean up
+        execute_query_fetch_all(self.evadb, drop_query)
+
     def run_create_function_query(self):
         create_function_query = """CREATE FUNCTION DummyObjectDetector
             INPUT  (Frame_Array NDARRAY UINT8(3, 256, 256))
@@ -136,6 +141,11 @@ def test_should_drop_function(self):
         )
         self.assertTrue(function is None)
 
+        # We should be able to re-create the function
+        self.run_create_function_query()
+        # clean up
+        execute_query_fetch_all(self.evadb, drop_query)
+
     def test_drop_wrong_function_name(self):
         self.run_create_function_query()
         right_function_name = "DummyObjectDetector"
@@ -227,3 +237,11 @@ def test_should_drop_database(self):
                 f"DROP DATABASE {database_name}",
                 do_not_print_exceptions=True,
             )
+
+        # We should be able to add the database again
+        execute_query_fetch_all(self.evadb, query)
+
+        # clean up
+        result = execute_query_fetch_all(
+            self.evadb, f"DROP DATABASE IF EXISTS {database_name}"
+        )