Best way to check duplication in database in c#

hj jh

Hi,

There are many scenario in c# that we need to verify for duplication check before saving records.
So I would like to know that if I have 1 database with 1 huge table filled with around 1-2 lac records say tblcustomer and if I want to check if the customer email ID in it is not duplicate then what is the best way of doing it.
Pls explain with some code if possible.
My .net application would be in c# , i may use ajax if required & backend would be sql server!

4 Replies

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hj jh14y ago
thank you all for answers.

But i think none of the answers are much satisfactory!
Because none of this ways are much efficient as far as large database is considered.
Yes I have already applied primary key to table but even after that it takes long & its not a efficient way to check for duplication in database & increase database transaction for this!
I am looking for some still better solution!
Krishna Garad14y ago
You may try this in sp

Create Procedure Sp_Check
(
@email Varchar(20),
@result Varchar(20) Out
)
As
Begin
if Exists(Select EmailId From TableName Where EmailId=@email)
Set @result='Already Available'
Else
Set @result='Not Available'
End
Sukesh Marla14y ago
if your table contains 1-2 lack records, then we should think

First make your column(for instance it is email id ) primary key or unique key.
Satyapriya Nayak14y ago
Hi,

Please refer the below links

http://www.aspdotnet-suresh.com/2011/03/how-to-check-username-availability.html

http://csharpdotnetfreak.blogspot.in/2012/05/check-username-email-availability-ajax.html

Thanks
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