How to control the User from inserting the same EIN(unique no. in db) and Primary Key violation?

[Vinod Vinu]

How to use the error handling properly so that i can avoid the primary key violation ?

Thanks in advance

[Ranveer K Kumar]

Vinod Vijay wrote:How to use the error handling properly so that i can avoid the primary key violation ?

Thanks in advance

1) You can set primary key as database/server side. which can be auto generated so user can not enter the duplicate value. (can be display on the form as read only field)
2) You can check the user entered value on server for duplication before inserting the record..

[Sagar Rohankar]

What is EIN ? Is it some kind of ID ? then ID is supposed to be created by DB.
If its anything other attribute than ID, then first you need to find out any row with that same EIN, if not present, enter one.