Prevent duplicate entry

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Views: 808 | Replies: 4

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Join Date: Nov 2007

Posts: 22

Reputation: chicago1985 is an unknown quantity at this point

Rep Power: 1

Solved Threads: 0

chicago1985 chicago1985 is offline

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Newbie Poster

Prevent duplicate entry

Dec 20th, 2007

I have my PHP inserting into Oracle 9i.
But how do I prevent duplicate record entries?

I only have 3 fields in the insert in the action page and my below attempt doesnt output anything or insert anything even if not a duplicate:

 Help with Code Tags 
 php Syntax (Toggle Plain Text) 
<?php
$c=OCILogon("scott", "tiger", "orcl");
  if ( ! $c ) {
    echo "Unable to connect: " . var_dump( OCIError() );
    die();
  }
$mydupcheck = "select * from personTable where firstname = $_POST[firstname] and lastname = $_POST[lastname] and emailaddress = $_POST[emailaddress]";
 
if($mydupcheck)
{
   echo "Duplicate entry";
}
else
{
$s = OCIParse($c, "INSERT INTO personTable (firstname,lastname,emailaddress) VALUES ($_POST[firstname],'$_POST[lastname]','$_POST[emailaddress]'");
OCIExecute($s, OCI_DEFAULT);
echo "Record successfully entered";
}
?>
<?php
$c=OCILogon("scott", "tiger", "orcl");
  if ( ! $c ) {
    echo "Unable to connect: " . var_dump( OCIError() );
    die();
  }
$mydupcheck = "select * from personTable where firstname = $_POST[firstname] and lastname = $_POST[lastname] and emailaddress = $_POST[emailaddress]";

if($mydupcheck)
{
   echo "Duplicate entry";
}
else
{
$s = OCIParse($c, "INSERT INTO personTable (firstname,lastname,emailaddress) VALUES ($_POST[firstname],'$_POST[lastname]','$_POST[emailaddress]'");
OCIExecute($s, OCI_DEFAULT);
echo "Record successfully entered";
}
?>

How do I prevent duplicate record info and show the user they entered duplicate info.

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Join Date: Dec 2007

Posts: 75

Reputation: hielo is an unknown quantity at this point

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Solved Threads: 10

hielo

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Junior Poster in Training

Re: Prevent duplicate entry

Dec 20th, 2007

The best approach is to have the DB enforce Referenctial Integrity. Basically you instruct the database at design time NOT to allow duplicates for certain records ever. IF such an attempt is made, the db server will not carry out the operation. Look at these:

http://www.google.com/search?hl=en&c...Oracle&spell=1

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Join Date: Dec 2007

Posts: 75

Reputation: hielo is an unknown quantity at this point

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hielo

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Junior Poster in Training

Re: Prevent duplicate entry

Dec 20th, 2007

The "hard" (and wrong) approach would be to first query the database to check for the existence of the record and insert it only if no record exists. But the right way to approach this is through referential integrity.

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Join Date: Nov 2007

Location: Bangalore, India

Posts: 3,098

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nav33n

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Posting Sensei

Re: Prevent duplicate entry

Dec 21st, 2007

•

Originally Posted by chicago1985

I have my PHP inserting into Oracle 9i.
But how do I prevent duplicate record entries?

I only have 3 fields in the insert in the action page and my below attempt doesnt output anything or insert anything even if not a duplicate:

There are some errors in your script.

$mydupcheck = "select * from personTable where firstname = $_POST[firstname] and lastname = $_POST[lastname] and emailaddress = $_POST[emailaddress]";

Since firstname, lastname and emailaddress are strings, you should put them in quotes. And btw, you are not executing that query.

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if($mydupcheck)
{
echo "Duplicate entry";
}

Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning.

*PM asking for help will be ignored*

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Join Date: Dec 2007

Posts: 75

Reputation: hielo is an unknown quantity at this point

Rep Power: 1

Solved Threads: 10

hielo

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Junior Poster in Training

Re: Prevent duplicate entry

Dec 23rd, 2007

Try this:

Help with Code Tags

(Toggle Plain Text)

<?php
$c=OCILogon("scott", "tiger", "orcl");
  if ( ! $c ) {
    echo "Unable to connect: " . var_dump( OCIError() );
    die();
  }

$sqlString = "select * from personTable where firstname='" . $_POST['firstname'] . "' and lastname='" . $_POST['lastname'] . "' and emailaddress='" . $_POST['emailaddress'] ."'");
$mydupcheck = OCIParse($c, $sqlString);

OCIExecute($mydupcheck);


$nrows = oci_fetch_all($mydupcheck, $results, 0, 1);


if($nrows)
{
   echo "Duplicate entry";
}
else
{
	$sqlString="INSERT INTO personTable (firstname,lastname,emailaddress) VALUES ('" . $_POST['firstname'] . "','" . $_POST['lastname'] . "','" . $_POST['emailaddress'] . "'";
	$s = OCIParse($c, $sqlString);
	OCIExecute($s, OCI_DEFAULT);
	echo "Record successfully entered";
}
?>