identical rows?

deep

Hello!

What is the best way to check a table and to see if there are several identical rows in it? If there are, then all but one should be deleted (only need one).

Thx 😃

Weedpacket

Do you mean a database table?

trippleweb

$sql=mysql_query("SELECT * FROM tablename")
or die("error");
while($myrow = mysql_fetch_array($sql))
{
$firstField=["firstField"];
$secondField=["secondField"];
$thirdField=["thirdField"];

$sql2=mysql_query["SELECT * FROM tablename WHERE firstField='$firstField' AND secondField='$secondField' AND thirdField='$thirdField'");
or die("error");
$duplicateRows = mysql_num_rows($sql2);

echo $myrow["firstField"]."has $duplicateRows duplicate entries";
}

Much easier if you disallowed duplicates

deep

Much easier if you disallowed duplicates

How do I do that?

Do you mean a database table?

Yes.

Thanks!

trippleweb

When I build a members database I do not want duplicate usernames:

//lets see if the username is already in database before inserting

$sql=mysql_query("SELECT * FROM members WHERE username=$sumbittedUsername`")
or die("error");

//this will count how many rows have the username
$rows = mysql_num_rows($sql);
if($rows>0)
{
//username already exists because we have more than 0 rows
$message="$sumbittedUsername already exists, please select another username";
include("form.php");
exit();
}
else
{
//we have zero rows, username does not exist, lets add them to the database
$sql=mysql_query("INSERT.....................
}