Hi when 2 users insert something at exact same moment

Question

Hi when 2 users insert something at exact same moment

(data which contain genrated alpha numeric id computed based on last inserted row eg. Last inserted row contain PUR1111 then new genrated number will be PUR1112).
When 2 user insert at exact moment they both get same PUR1112,
Wheb they insert with millisecond differences it is working fine.
How to solve it?

0

04.09.2019