feat(dbt): add intermediate returns transformation models

Author: Ritik574-coder

models/intermediate/Returns/int_return_processing.sql

@@ -1,9 +1,39 @@
 SELECT
     return_id,
-    return_reason,
-    return_channel,
-    restocked,
-    return_status,
-    handled_by_emp_id,
-    notes
-FROM {{ ref('stg_returns') }} ;
+
+    CASE 
+          WHEN return_reason IS NULL OR TRIM(return_reason) = '' THEN 'Unknown'
+          ELSE TRIM(dbo.TitleCase(return_reason))
+    END as return_reason,
+
+    CASE 
+        WHEN TRIM(LOWER(return_channel)) IN ('app', 'mobile app', 'mobile')   THEN 'Mobile App'
+        WHEN TRIM(LOWER(return_channel)) IN ('in store', 'in-store', 'store') THEN 'In Store'
+        WHEN TRIM(LOWER(return_channel)) IN ('online', 'web')                 THEN 'Online'
+        WHEN TRIM(LOWER(return_channel)) = 'phone'                            THEN 'Phone Call'
+        WHEN TRIM(LOWER(return_channel)) = 'catalog'                          THEN 'Catalog'
+        ELSE 'Unknown'
+    END AS return_channel,
+    
+    CASE 
+          WHEN TRIM(LOWER(restocked)) IN ('yes', 'y', '1') THEN 'Yes'
+          WHEN TRIM(LOWER(restocked)) IN ('no', 'n', '0')  THEN 'No'
+          ELSE 'Unknown'
+    END AS restocked,
+
+    CASE 
+          WHEN return_status IS NULL THEN 'Unknown'
+          ELSE TRIM(dbo.TitleCase(return_status))
+    END as return_status,
+
+    CASE 
+          WHEN handled_by_emp_id IS NULL OR TRY_CONVERT(INT, handled_by_emp_id) IS NULL THEN NULL 
+          ELSE TRY_CONVERT(INT, handled_by_emp_id)
+    END as handled_by_emp_id,
+
+    CASE 
+          WHEN notes IS NULL OR LEN(TRIM(notes)) < 3 OR TRIM(notes) = '' THEN 'Unknown'
+          ELSE TRIM(dbo.TitleCase(REPLACE(REPLACE(notes, CHAR(10), ''), CHAR(13), '')))
+    END as notes
+FROM {{ ref('stg_returns') }} ;
+

models/intermediate/Returns/int_return_refund.sql

@@ -1,5 +1,15 @@
 SELECT 
     return_id,
-    refund_amount,
-    refund_method
-FROM {{ ref('stg_returns') }} ;
+    
+    CASE 
+          WHEN TRY_CONVERT(DECIMAL(10, 2), REPLACE(REPLACE(refund_amount, ',', ''), '$', '')) IS NULL THEN NULL
+          WHEN refund_amount IS NULL OR TRY_CONVERT(DECIMAL(10, 2), REPLACE(REPLACE(refund_amount, ',', ''), '$', '')) < 0 THEN NULL 
+          ELSE TRY_CONVERT(DECIMAL(10, 2), REPLACE(REPLACE(refund_amount, ',', ''), '$', ''))
+    END as refund_amount,
+
+    CASE 
+          WHEN refund_method IS NULL OR TRIM(refund_method) = '' THEN 'Unknown'
+          ELSE TRIM(dbo.TitleCase(refund_method))
+    END as refund_method
+FROM {{ ref('stg_returns') }} ;
+

models/intermediate/Returns/int_return_transaction.sql

@@ -1,11 +1,58 @@
 SELECT
-    return_id,
-    original_txn_id,
-    original_order_id,
-    customer_id,
-    customer_name,
-    product_id,
-    product_name,
-    quantity_returned,
-    return_date
-FROM {{ ref('stg_returns') }} ;
+    CASE 
+          WHEN TRY_CONVERT(INT, return_id) < 1 OR TRY_CONVERT(INT, return_id) IS NULL THEN NULL 
+          ELSE TRY_CONVERT(INT, return_id)
+    END as return_id,
+
+    CASE 
+          WHEN original_txn_id IS NULL THEN NULL
+          WHEN UPPER(TRIM(original_txn_id)) NOT LIKE 'TXN-%' THEN NULL
+          WHEN LEN(UPPER(TRIM(original_txn_id))) < 10 THEN NULL
+          ELSE UPPER(TRIM(original_txn_id))
+    END as original_txn_id,
+
+    CASE 
+          WHEN original_order_id IS NULL OR TRY_CONVERT(INT, original_order_id) < 1 OR TRY_CONVERT(INT, original_order_id) IS NULL THEN NULL 
+          ELSE TRY_CONVERT(INT, original_order_id)
+    END as original_order_id,
+
+    CASE 
+          WHEN customer_id IS NULL OR TRY_CONVERT(INT, customer_id) IS NULL THEN NULL 
+          ELSE TRY_CONVERT(INT, customer_id)
+    END as customer_id,
+
+    CASE 
+          WHEN customer_name IS NULL OR TRIM(customer_name) = '' THEN 'Unknown'
+          ELSE dbo.TitleCase(TRIM(customer_name))
+    END as customer_name,
+
+    CASE 
+          WHEN product_id IS NULL OR TRY_CONVERT(INT, product_id) IS NULL THEN NULL 
+          ELSE TRY_CONVERT(INT, product_id)
+    END as product_id,
+
+    CASE 
+          WHEN product_name IS NULL OR TRIM(product_name) = '' THEN 'Unknown'
+          ELSE dbo.TitleCase(TRIM(product_name))
+    END as product_name,
+
+    CASE 
+          WHEN quantity_returned IS NULL OR TRY_CONVERT(INT, quantity_returned) IS NULL OR TRY_CONVERT(INT, quantity_returned) < 1 THEN NULL 
+          ELSE TRY_CONVERT(INT, quantity_returned)
+    END as quantity_returned,
+
+    CASE 
+        WHEN return_date LIKE '[A-Z][a-z][a-z][a-z] __, ____' THEN TRY_CONVERT(DATE ,return_date)
+        WHEN return_date LIKE '[A-Z][a-z][a-z] __, ____'      THEN TRY_CONVERT(DATE ,return_date)
+        WHEN return_date LIKE '____/__/__'                    THEN TRY_CONVERT(DATE ,return_date)
+        WHEN return_date LIKE '____-__-__'                    THEN TRY_CONVERT(DATE ,return_date)
+
+        WHEN return_date LIKE '__/__/____' AND TRY_CONVERT(INT, SUBSTRING(return_date, 4, 2)) > 12 THEN TRY_CONVERT(DATE, return_date, 101)
+        WHEN return_date LIKE '__/__/____' AND TRY_CONVERT(INT, LEFT(return_date, 2))         > 12 THEN TRY_CONVERT(DATE, return_date, 103)
+        WHEN return_date LIKE '__-__-____' AND TRY_CONVERT(INT, SUBSTRING(return_date, 4, 2)) > 12 THEN TRY_CONVERT(DATE, return_date, 110)
+        WHEN return_date LIKE '__-__-____' AND TRY_CONVERT(INT, LEFT(return_date, 2))         > 12 THEN TRY_CONVERT(DATE, return_date, 105)
+        ELSE TRY_CONVERT(DATE, return_date)
+    END as return_date
+FROM {{ ref('stg_returns') }} ;
+
+