relax uniqueness and drop simple dup rows

cal-itp · Oct 2, 2023 · 9471423 · 9471423
1 parent 72f78c8
commit 9471423
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Showing 3 changed files with 38 additions and 11 deletions.
diff --git a/warehouse/macros/littlepay_staging_transforms.sql b/warehouse/macros/littlepay_staging_transforms.sql
@@ -32,17 +32,17 @@ CASE
 END
 {% endmacro %}
 
-{% macro qualify_dedupe_lp_files(file_dt_col = 'littlepay_export_date', file_ts_col = 'littlepay_export_ts', ts_col = 'ts') %}
+{% macro qualify_dedupe_lp_files(instance_col = 'instance', file_dt_col = 'littlepay_export_date', file_ts_col = 'littlepay_export_ts', ts_col = 'ts') %}
 
 -- remove duplicate instances of the same file (file defined as date-level update from LP)
 -- partition by file date, order by LP-defined timestamp (most recent first), and then order by our extract timestamp (most recent first)
 -- use dense rank instead of row number because we need to allow all rows from a given file to be included (allow ties)
 QUALIFY DENSE_RANK()
-    OVER (PARTITION BY {{ file_dt_col }} ORDER BY {{ file_ts_col }} DESC, {{ ts_col }} DESC) = 1
+    OVER (PARTITION BY {{ instance_col }}, {{ file_dt_col }} ORDER BY {{ file_ts_col }} DESC, {{ ts_col }} DESC) = 1
 
 {% endmacro %}
 
-{% macro qualify_dedupe_lp_rows(content_hash_col = 'content_hash', file_ts_col = 'littlepay_export_ts', line_number_col = '_line_number') %}
+{% macro qualify_dedupe_full_duplicate_lp_rows(content_hash_col = 'content_hash', file_ts_col = 'littlepay_export_ts', line_number_col = '_line_number') %}
 
 -- remove full duplicate rows where *all* content is the same
 -- get most recent instance across files and then highest-line-number instance within most recent file

diff --git a/warehouse/models/staging/payments/littlepay/_littlepay.yml b/warehouse/models/staging/payments/littlepay/_littlepay.yml
@@ -181,13 +181,13 @@ models:
         tests:
           - not_null
           - unique
-      - &payments_natural_key
-        name: _payments_key
+      - name: _payments_key
         description: |
           Synthentic key composed of the elements that define a natural key within the source data (primary key according to Littlepay schema.)
         tests:
           - not_null
-          - unique
+          - unique_proportion:
+              at_least: 0.999
 
   - name: stg_littlepay__customer_funding_source
     tests:

diff --git a/warehouse/models/staging/payments/littlepay/stg_littlepay__authorisations.sql b/warehouse/models/staging/payments/littlepay/stg_littlepay__authorisations.sql
@@ -39,9 +39,35 @@ clean_columns_and_dedupe_files AS (
             'retrieval_reference_number', 'littlepay_reference_number', 'external_reference_number',
             'response_code', 'status', 'authorisation_date_time_utc']) }} AS content_hash,
     FROM source
+    -- drop extra header rows
+    WHERE aggregation_id != "aggregation_id"
     {{ qualify_dedupe_lp_files() }}
 ),
 
+add_keys_drop_full_dupes AS (
+    SELECT
+        *,
+        -- generate keys now that input columns have been trimmed & cast and files deduped
+        {{ dbt_utils.generate_surrogate_key(['littlepay_export_date', '_line_number', 'instance']) }} AS _key,
+        {{ dbt_utils.generate_surrogate_key(['aggregation_id', 'authorisation_date_time_utc']) }} AS _payments_key,
+    FROM clean_columns_and_dedupe_files
+    {{ qualify_dedupe_full_duplicate_lp_rows() }}
+),
+
+-- we have some authorisations where the same aggregation has multiple rows with the same timestamp
+-- these seem like clear duplicates, and some of them one of the two copies is missing status and RRN; these can be dropped
+-- the rest need to be handled downstream by checking against settlements data
+same_timestamp_simple_dupes AS (
+    SELECT
+        _payments_key,
+        TRUE AS to_drop,
+        COUNT(DISTINCT retrieval_reference_number) AS ct_rrn,
+        COUNT(*) AS ct
+    FROM add_keys_drop_full_dupes
+    GROUP BY 1
+    HAVING ct > 1 AND ct_rrn = 1
+),
+
 stg_littlepay__authorisations AS (
     SELECT
         participant_id,
@@ -62,11 +88,12 @@ stg_littlepay__authorisations AS (
         littlepay_export_ts,
         littlepay_export_date,
         ts,
-        {{ dbt_utils.generate_surrogate_key(['littlepay_export_date', '_line_number', 'instance']) }} AS _key,
-        {{ dbt_utils.generate_surrogate_key(['aggregation_id', 'authorisation_date_time_utc']) }} AS _payments_key,
-    FROM clean_columns_and_dedupe_files
-    {{ qualify_dedupe_lp_rows() }}
-
+        _key,
+        _payments_key,
+    FROM add_keys_drop_full_dupes
+    LEFT JOIN same_timestamp_simple_dupes
+    USING(_payments_key)
+    WHERE NOT COALESCE(to_drop, FALSE)
 )
 
 SELECT * FROM stg_littlepay__authorisations