How add more rows when find string in column Oracle - sql

Question

Would it be possible to add more rows base on Keyword string in SQL ?
table A
PID PromotionName
1 OUT_EC_D10_V500K_FamilyCare_PROCO
2 OUT_EC_D5_V50K_Lunchbox_PROCO
3 OUT_EC_D5_V50K_PROCO
table B
promotion_code itm_name quantity
Lunchbox Item name 1 1
FamilyCare Item name 2 1
FamilyCare Item name 3 1
BUY1FREE6 Item name 4 1
HiSummer Item name 5 1
FamilyCare Item name 6 1
Example:
SELECT * FROM A where pid = '1';
Output of the SQL should be -
PID PromotionName Itm_name quantity
1 OUT_EC_D10_V500K_FamilyCare_PROCO
2 FamilyCare Item name 2 1
3 FamilyCare Item name 3 1
4 FamilyCare Item name 6 1
How to find string with keyword 'FamilyCare' in PromotionName of table A base on promotion_code of table B? If it exist it will add more rows in output
Any help with the SQL?

Answer 1

Here is how you can achieve this:
SELECT PID,PromotionName, '' as Itm_name, NULL as quantity
FROM A
WHERE pid = '1'
UNION
SELECT PID, PROMOTION_NAME, Itm_name, quantity
FROM
(SELECT * FROM A inner join B on a.promotionName LIKE '%'||b.promotion_name||'%')
WHERE pid='1'
You have to update your pid in both the places (before and after UNION).
Notice that tables were joined using LIKE operator with % before and after the word. Hence this joins if a part of a string is present in another column.
db<>fiddle link here

Answer 2

An option would be starting to construct a subquery factoring along with joining tables through a.promotionName LIKE '%'||b.promotion_code||'%' condition while filtering by b.promotion_code = 'FamilyCare', then add another query to combine the result sets by UNION ALL, and then enumerate with an id column by ROW_NUMBER() analytic function such as
WITH ab AS
(
SELECT a.*, b.*
FROM a
JOIN b
ON a.promotionName LIKE '%'||b.promotion_code||'%'
WHERE b.promotion_code = 'FamilyCare'
), ab2 AS
(
SELECT promotion_code, itm_name, quantity
FROM ab
UNION ALL
SELECT DISTINCT promotionName, NULL, NULL
FROM ab
)
SELECT ROW_NUMBER() OVER (ORDER BY itm_name NULLS FIRST) AS pid,
a.*
FROM ab2 a
if there's mismatch for the topmost query, then no row will be returned. eg. that query will check for the existence for the literal you provide
Demo