DRY on stg cosmos db models

macros/cosmos_db_utils.sql

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+{% macro cosmos_db_record_deduplication(source_table, primary_key) %}
+    /*
+This macro provides a deduplication logic for Cosmos DB entities.
+If two or more records have a duplicated value in a field that acts as 
+the primary key, the most recent record will be returned. If the record
+is not duplicated, it will also be returned.
+
+Inputs:
+    - source_table: table that acts as source. Should be a sync model.
+    - primary_key: unique identifier on which the deduplication will be applied.
+Output:
+    - Returns the set of records from the source_table that are unique according 
+      to the primary_key. 
+*/
+    select *
+    from
+        -- Some thoughts for the future here:
+        -- The query below is awful performance wise - but data 
+        -- size is tiny today. Let's tackle the problem as it comes.
+        (
+            select
+                *,
+                row_number() over (
+                    partition by
+                        {{ adapter.quote("documents") }} ->> '{{ primary_key }}'
+                    order by ({{ adapter.quote("documents") }} ->> '_ts')::integer desc
+                ) as rank
+            from {{ source_table }}
+        )
+    where rank = 1
+{% endmacro %}