UNIQUE index and duplicate error

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UNIQUE index and duplicate error

Author

Topic

fluvly
Starting Member

2 Posts

Posted - 2009-01-15 : 08:52:09

Hi everyone,

I have just created a UNIQUE index on a "username" field. Obviously, when I try to register a new user with an already existing username, the query doesn't succeed.

What I would like to know is whether there is a way for php to detect that the query doesn't succeed for that precise reason and not for a server issue... so that it would reload the "user registration" page with the error "username already in database" written on top. How can I achieve that?

Thank you for any help.

Flaviana

visakh16
Very Important crosS Applying yaK Herder

52326 Posts

Posted - 2009-01-15 : 08:56:04

just check before insertion if username already exist and raiserror if it does like


IF EXISTS(SELECT 1 FROM table WHERE username=@yourvalue)
 RAISERROR ('username already in database',10,1)
ELSE
insert code here...

sakets_2000
Master Smack Fu Yak Hacker

1472 Posts

Posted - 2009-01-15 : 08:56:20

you can have sql to check if userid is already in the table
something like,

if exists(select 1 from yourtable  where username=<username>)
print 'It already exists'
else 
....

Lumbago
Norsk Yak Master

3271 Posts

Posted - 2009-01-15 : 08:56:59

You'll have to capture it manually...something like this might work:

IF EXISTS (SELECT Username FROM table WHERE Username = @username)
  RAISERROR('Username allready exists', 16, 1)
ELSE
  INSERT INTO table () ...

- Lumbago

Lumbago
Norsk Yak Master

3271 Posts

Posted - 2009-01-15 : 08:58:13

OMG! 3 almost identical replies within one minute!

- Lumbago

visakh16
Very Important crosS Applying yaK Herder

52326 Posts

Posted - 2009-01-15 : 09:01:08

quote:
Originally posted by Lumbago

OMG! 3 almost identical replies within one minute!

- Lumbago

Wow! I'm winner by 16 s

fluvly
Starting Member

2 Posts

Posted - 2009-01-15 : 09:07:28

Thank you all very much!

visakh16
Very Important crosS Applying yaK Herder

52326 Posts

Posted - 2009-01-15 : 09:08:44

welcome

Lumbago
Norsk Yak Master

3271 Posts

Posted - 2009-01-15 : 09:13:14

If I only didn't test mine first...bummer!! Hehe, I couldn't remember if the level/state of raiserror came before or after the message

- Lumbago

visakh16
Very Important crosS Applying yaK Herder

52326 Posts

Posted - 2009-01-15 : 23:54:11

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