How can I get this pivot kind of output in sql - mysql

Question

Consider my source table as given below i.e customer.
How can i get the required output as shown using sql (oracle or mysql)
customer :
customer id Purchase_id cashback
123 abc111 5
123 abc112 5
123 abc113 2
345 abc311 0
345 abc312 2
678 abc611 4
678 abc612 3
678 abc613 5
Output Needed:
ID purchare_id_1 purchare_id_2 purchare_id_3 cashback_1 cashback_2 cashback_3
123 abc111 abc112 abc113 5 5 2
345 abc311 abc312 0 2
678 abc611 abc612 abc613 4 3 5
DML and DDL:
create table cust_table (
customer_id int, Purchase_id varchar(100), cashback int
);
insert into cust_table values
(123 , 'abc111' , 5),
(123 , 'abc112' , 5),
(123 , 'abc113' , 2),
( 345 , 'abc311' , 0),
(345 , 'abc312' , 2),
(678 , 'abc611' , 4),
(678 , 'abc612' , 3),
(678 , 'abc613' , 5);
commit;
PS:
Data might be not static, it can change.

Answer 1

WITH
cte AS ( SELECT *, ROW_NUMBER() OVER (PARTITION BY customer_id ORDER BY Purchase_id) rn
FROM cust_table )
SELECT customer_id,
MAX(CASE WHEN rn=1 THEN Purchase_id END) purchase_1,
MAX(CASE WHEN rn=2 THEN Purchase_id END) purchase_2,
MAX(CASE WHEN rn=3 THEN Purchase_id END) purchase_3,
MAX(CASE WHEN rn=1 THEN cashback END) cashback_1,
MAX(CASE WHEN rn=2 THEN cashback END) cashback_2,
MAX(CASE WHEN rn=3 THEN cashback END) cashback_3
FROM cte
GROUP BY customer_id
https://dbfiddle.uk/?rdbms=mysql_8.0&fiddle=ec2de721d7089a82a5f7ae669ce2d19e

Answer 2

In MySQL: You can use concat along with group by to see partial result like as below
select customer_id, group_concat(`Purchase_id` separator ',') as `Purchase_idX`,
group_concat(`cashback` separator ',') as `cashbackX` from cust_table
group by customer_id;
If you want the exact result run the below query:
select
SUBSTRING_INDEX(AA, ',', 1) as purchare_id_1,
CASE
WHEN LOCATE(',', AA, 2) = 0 THEN NULL
ELSE SUBSTRING_INDEX(SUBSTRING_INDEX(AA, ',', 2), ',', -1)
END AS purchare_id_2,
CASE
WHEN LOCATE(',', AA, LOCATE(',', AA, 1)+1) = 0 THEN NULL
ELSE SUBSTRING_INDEX(SUBSTRING_INDEX(AA, ',', 3), ',', -1)
END AS cashback_1,
SUBSTRING_INDEX(BB, ',', 1) as purchare_id_1,
CASE
WHEN LOCATE(',', BB, 2) = 0 THEN NULL
ELSE SUBSTRING_INDEX(SUBSTRING_INDEX(BB, ',', 2), ',', -1)
END AS cashback_2,
CASE
WHEN LOCATE(',', BB, LOCATE(',', BB, 1)+1) = 0 THEN NULL
ELSE SUBSTRING_INDEX(SUBSTRING_INDEX(BB, ',', 3), ',', -1)
END AS cashback_3
from
( select customer_id, group_concat(`Purchase_id` separator ',') as AA, group_concat(`cashback` separator ',') as BB,
group_concat(`cashback` separator ',') as `cashbackX` from cust_table
group by customer_id) as TB