From f42ab4a7e043a8a9e35c1fefadd42554a59836f4 Mon Sep 17 00:00:00 2001
From: Septimiu Turcu <septimiu.turcu@teradata.com>
Date: Thu, 5 Sep 2024 02:38:31 +0200
Subject: [PATCH 1/2] Update code for create_columns and get_true_sql macros

---
 .../materializations/snapshot/helpers.sql     | 21 ++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/dbt/include/teradata/macros/materializations/snapshot/helpers.sql b/dbt/include/teradata/macros/materializations/snapshot/helpers.sql
index 6ba36453..6c51c494 100644
--- a/dbt/include/teradata/macros/materializations/snapshot/helpers.sql
+++ b/dbt/include/teradata/macros/materializations/snapshot/helpers.sql
@@ -1,3 +1,19 @@
+{% macro teradata__create_columns(relation, columns) %}
+  {% for column in columns %}
+    {% call statement() %}
+      alter table {{ relation.render() }} add "{{ column.name }}" {{ column.data_type }};
+    {% endcall %}
+  {% endfor %}
+{% endmacro %}
+
+{% macro teradata__post_snapshot(staging_relation) %}
+    {{ adapter.dispatch('drop_relation', 'dbt')(staging_relation) }}
+{% endmacro %}
+
+{% macro teradata__get_true_sql() %}
+    {{ return('1 = 1') }}
+{% endmacro %}
+
 {% macro teradata__snapshot_staging_table(strategy, source_sql, target_relation) -%}
 
     with snapshot_query as (
@@ -125,8 +141,3 @@
     ) sbq
 
 {% endmacro %}
-
-{% macro teradata__post_snapshot(staging_relation) %}
-    {{ adapter.dispatch('drop_relation', 'dbt')(staging_relation) }}
-{% endmacro %}
-

From 421c5e9da897fc7c1fed31f39cf6235bb7369a08 Mon Sep 17 00:00:00 2001
From: Varun Sharma <varun1598sharma@gmail.com>
Date: Wed, 13 Nov 2024 12:15:26 +0530
Subject: [PATCH 2/2] testcase for snapshot with schema change

---
 .../snapshot_on_schema_change.py              | 56 +++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100644 tests/functional/adapter/simple_snapshot/snapshot_on_schema_change.py

diff --git a/tests/functional/adapter/simple_snapshot/snapshot_on_schema_change.py b/tests/functional/adapter/simple_snapshot/snapshot_on_schema_change.py
new file mode 100644
index 00000000..7a2976e8
--- /dev/null
+++ b/tests/functional/adapter/simple_snapshot/snapshot_on_schema_change.py
@@ -0,0 +1,56 @@
+import pytest
+from dbt.tests.util import run_dbt
+
+seeds_base_csv = """
+id,name,some_date
+1,Easton,1981-05-20T06:46:51
+2,Lillian,1978-09-03T18:10:33
+3,Jeremiah,1982-03-11T03:59:51
+4,Nolan,1976-05-06T20:21:35
+5,Hannah,1982-06-23T05:41:26
+6,Eleanor,1991-08-10T23:12:21
+7,Lily,1971-03-29T14:58:02
+8,Jonathan,1988-02-26T02:55:24
+9,Adrian,1994-02-09T13:14:23
+10,Nora,1976-03-01T16:51:39
+""".lstrip()
+
+ts_snapshot_sql = """
+{% snapshot ts_snapshot %}
+    {{ config(
+        strategy='timestamp',
+        unique_key='id',
+        updated_at='some_date',
+        target_database=database,
+        target_schema=schema,
+    )}}
+    select * from {{ ref(var('seed_name', 'base')) }}
+{% endsnapshot %}
+""".strip()
+
+
+class TestSnapshotOnSchemaChange:
+    @pytest.fixture(scope="class")
+    def seeds(self):
+        return {
+            "base.csv": seeds_base_csv,
+        }
+
+    @pytest.fixture(scope="class")
+    def snapshots(self):
+        return {
+            "ts_snapshot.sql": ts_snapshot_sql,
+        }
+
+    def test_snapshot_on_schema_change(self, project):
+        # seed command
+        results = run_dbt(["seed"])
+
+        # snapshot command
+        results = run_dbt(["snapshot"])
+
+        project.run_sql("ALTER TABLE {schema}.base ADD last_initial varchar(30)");
+
+        results = run_dbt(["seed"])
+
+        results = run_dbt(["snapshot"])