sql query command question

[Kudo]

i have some question guys!.. 

This is my query in some script
query_sql "UPDATE go_premium SET `expiration_date` = DATE_ADD(NOW(), INTERVAL 7 DAY) WHERE `account_id` = "+ getcharid(3) +"";

it works fine for me but my question is how can i change the "DATE_ADD(NOW(), INTERVAL 7 DAY" to  the value of the expiration date table + 7 days can someone teach me some tricks?

[Patskie]

Change

DATE_ADD(NOW(), INTERVAL 7 DAY)

To

COALESCE(DATE_ADD(`expiration_date`, INTERVAL 7 DAY), DATE_ADD(NOW(), INTERVAL 7 DAY))

 

Edited August 9, 2020 by Patskie

[Kudo]

On 8/9/2020 at 2:07 PM, Patskie said:

Change

DATE_ADD(NOW(), INTERVAL 7 DAY)

To

COALESCE(DATE_ADD(`expiration_date`, INTERVAL 7 DAY), DATE_ADD(NOW(), INTERVAL 7 DAY))

 

why do i need to  add the date_add(now(), interval 7 day)) on the last part?
DATE_ADD(NOW(), INTERVAL 7 DAY)) is for new record right ? correct me if im wrong
i just need to update the the expiration_date to 7 more days when i click some items...

i can 

i found some error when trying the script sir... please help me 

sorry for the post but i manage to fixed it.. i forgot to add the other codes... thanks anyway @Patskie