cleaning and standeardization custoemr table and handling datyaissues

Co-authored-by: ritsky-project <ritsky598@gmail.com>

Author: Ritik574-coder

explore_database/returns/return.sql

@@ -83,7 +83,9 @@ WITH cleaned_txn_ids AS
 (
       SELECT 
             CASE 
-                  WHEN original_txn_id IS NULL OR original_txn_id  NOT LIKE 'TXN-%' OR LEN(original_txn_id) < 10 THEN NULL 
+                  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
       FROM bronze.[returns] 
@@ -180,7 +182,7 @@ WITH cleaned_customer_names AS
 (
       SELECT 
             CASE 
-                  WHEN customer_name IS NULL OR customer_name != TRIM(dbo.TitleCase(customer_name))  OR LEN(customer_name) < 3 THEN 'Unknown'
+                  WHEN customer_name IS NULL OR TRIM(customer_name) = '' THEN 'Unknown'
                   ELSE dbo.TitleCase(TRIM(customer_name))
             END as customer_name
       FROM bronze.[returns] 
@@ -235,17 +237,19 @@ FROM
 (
       SELECT 
             CASE 
-                  WHEN return_id < 1 OR TRY_CONVERT(INT, return_id) IS NULL THEN NULL 
+                  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 OR original_txn_id  NOT LIKE 'TXN-%' OR LEN(original_txn_id) < 10 THEN NULL 
+                  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) IS NULL THEN NULL 
+                  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
 
@@ -255,7 +259,7 @@ FROM
             END as customer_id
 
             ,CASE 
-                  WHEN customer_name IS NULL OR customer_name != TRIM(dbo.TitleCase(customer_name))  OR LEN(customer_name) < 3 THEN 'Unknown'
+                  WHEN customer_name IS NULL OR TRIM(customer_name) = '' THEN 'Unknown'
                   ELSE dbo.TitleCase(TRIM(customer_name))
             END as customer_name