Added a macro to update dbt_scd_id

Author: aosingh

dbt/include/oracle/macros/materializations/snapshot/snapshot.sql

@@ -164,7 +164,7 @@
         {{ strategy.scd_id }} as dbt_scd_id,
         {{ strategy.updated_at }} as dbt_updated_at,
         {{ strategy.updated_at }} as dbt_valid_from,
-        cast(nullif({{ strategy.updated_at }}, {{ strategy.updated_at }}) as TIMESTAMP) as dbt_valid_to
+        cast(nullif({{ strategy.updated_at }}, {{ strategy.updated_at }}) as TIMESTAMP(9)) as dbt_valid_to
     from (
         {{ sql }}
     ) sbq

dbt/include/oracle/macros/update_legacy_snapshots.sql

@@ -0,0 +1,70 @@
+{#
+ Copyright (c) 2024, Oracle and/or its affiliates.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+     https://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+#}
+
+{#
+ Legacy hash function ORA_HASH is known to have collisions in large datasets
+ causing errors in snapshot merge statement. Please check the below Github
+ issues:
+
+    https://github.com/oracle/dbt-oracle/issues/52
+    https://github.com/oracle/dbt-oracle/issues/102
+
+This hash function is used in the marcro oracle__snapshot_hash_arguments
+
+dbt-oracle 2.0 will switch to a stronger hash function - SHA256. Changing the
+hash function will invalidate existing snapshots.These helper macros will
+ensure a smoother transition to dbt-oracle 2.0.
+
+It is recommended for teams to switch to SHA256 hash function before
+dbt-oracle 2.0 using a 2-step process:
+1. Create a macro oracle__snapshot_hash_arguments(args) in your dbt project
+   Copy paste the contents of macro
+   oracle__snapshot_standard_hash_arguments(args) shown below. This will become
+   the default from dbt-oracle 2.0
+
+2. Run the following operation on your snapshot table
+
+dbt --debug run-operation update_legacy_dbt_scd_id \
+    --args '{snapshot_table: PROMOTION_COSTS_SNAPSHOT, cols: ["promo_id", "dbt_updated_at"]}'
+
+#}
+
+{% macro oracle__snapshot_standard_hash_arguments(args) -%}
+    STANDARD_HASH({%- for arg in args -%}
+        coalesce(cast({{ arg }} as varchar(4000) ), '')
+        {% if not loop.last %} || '|' || {% endif %}
+    {%- endfor -%}, 'SHA256')
+{%- endmacro %}
+
+
+{% macro update_legacy_dbt_scd_id(snapshot_table, cols) -%}
+
+   {%- call statement('update_legacy_dbt_scd_id_dtype') -%}
+    BEGIN
+        UPDATE {{ snapshot_table }} SET DBT_SCD_ID = NULL;
+        COMMIT;
+        EXECUTE IMMEDIATE 'ALTER TABLE {{ snapshot_table }} MODIFY (dbt_scd_id RAW(32))';
+    END;
+    {%- endcall -%}
+
+    {%- call statement('update_legacy_dbt_scd_id') -%}
+    BEGIN
+        UPDATE {{ snapshot_table }}
+        SET dbt_scd_id = {{ oracle__snapshot_standard_hash_arguments(cols) }};
+        COMMIT;
+    END;
+    {%- endcall -%}
+{%- endmacro %}

requirements.txt

@@ -1,4 +1,4 @@
 dbt-common>=1.1.0,<2.0
 dbt-adapters>=1.2.1,<2.0
 dbt-core>=1.8.1,<2.0
-oracledb==2.5.0
+oracledb==2.5.1

setup.cfg

@@ -35,7 +35,7 @@ install_requires =
     dbt-common>=1.1.0,<2.0
     dbt-adapters>=1.2.1,<2.0
     dbt-core~=1.8,<1.9
-    oracledb==2.5.0
+    oracledb==2.5.1
 test_suite=tests
 test_requires =
     dbt-tests-adapter~=1.8,<1.9

setup.py

@@ -43,7 +43,7 @@
         "dbt-common>=1.1.0,<2.0",
         "dbt-adapters>=1.2.1,<2.0",
         "dbt-core~=1.8,<1.9",
-        "oracledb==2.5.0"
+        "oracledb==2.5.1"
 ]
 
 test_requirements = [