This question may seem very very easy (Select COUNT(Id), but in my case is different. I developed a web application with 15 to 25 concurrent users. every time they open the program, I am checking the last row inserted into the database and in C# I created a serial number based on the last row inserted + 1. So say for example below entry:
User1 opens up the program:
DB count = 1
C# Series = Ser-00001 (displayed in UI)
User1 inserts a row. success
User2 opens up the program:
DB count = 2
C# Series = Ser-00002 (displayed in UI)
User2 inserts a row. success
User3 opens up the program:
DB count = 3
C# Series = Ser-00003 (displayed in UI)
User3 inserts a row. success
No issue right? But, there will be a time that 2 or more users will open the program at the same time. Now, below is the scenario
User7 opens up the program:
DB count = 4
C# Series = Ser-00004 (displayed in UI)
User7 inserts a row. success
User8 opens up the program:
DB count = 4
C# Series = Ser-00004 (displayed in UI)
User8 inserts a row. failed
User9 opens up the program:
DB count = 4
C# Series = Ser-00004 (displayed in UI)
User9 inserts a row. failed
This time a big problem suddenly occur!
Now my question is, how do you do it to avoid this type of duplication? Thank you in advance for any posible solution.

Siddharth GajbhiyePosted Apr 7, 2021, 4:06 AM
Jes SiePosted Apr 26, 2021, 1:45 AM
Sachin SinghPosted Apr 7, 2021, 8:01 AM
Jignesh KumarPosted Apr 7, 2021, 3:38 AM
Sundaram SubramanianPosted Apr 7, 2021, 2:05 AM
Salman BegPosted Apr 6, 2021, 6:09 PM