No database connection with no errors
Question
I have Ubuntu 16.10 x86_64 x86_64. I installed LAMP to program in PHP and to create databases. In my php program I want to connect to my local database for creating a table ( in HTML ) with the data of any row of the table. The problem is that when I open the php file( localhost/file.php ) through firefox ,the browser doesn't charge anything. If thare were been an error during the connection with the database, It would have printed something in the browser. Here the code:
<!DOCTYPE html>
<html>
<head><title> SQL & PHP </title></head>
<body>
<?php
$db = mysql_connect("localhost", "root", "password")
or die ("Non riesco a creare la connessione");
mysql_select_db("scuola")
or die ("Non trovo il DB");
$sql = "SELECT id_utente, nome_utente, password_utente, conta_pres FROM utenti WHERE conta_pres <> 0";
$ris = mysql_query($sql) or die ("Query fallita!");
echo "<TABLE><TR><TH>ID utente <TH> Nome utente <TH>Password<TH>Contatore visite</TR>";
while ($riga= mysql_fetch_array($ris))
{
echo ("<TR>");
echo "<TD>" . $riga["id_utente"];
echo "<TD>" . $riga["nome_utente"];
echo "<TD>" . $riga["password_utente"];
echo "<TD>" . $riga["conta_pres"];
}
mysql_close();
?>
</body>
</html>
I checked the syntax (using a website) of the code and thare aren't problems,even because I copied this one by a book. I read that mysql_connect has been deprecated, so I replaced it with new mysqli_connect but the error still remains: white page. I tried to put 2 echo, one before the connecting function and one after that. Only the first echo is printed on the screen. I tried to type in the terminal sudo apt-get install php5-mysql but there is an error: The "php5-mysql" packet has not run to install
Can someone help me, please?
1 answers
solution1
1 2017-04-19 15:20:02
First of all use mysqli instead of mysql .
I think I have found the problem. When you call mysqli_select_db , it expects 2 parameters and you only specified one. Even though you have set the $db database connection, you need to specify which database you want to select the database name from.
So mysqli_select_db($db, "scuola") should do the trick.
And at the bottom close the connection specifying which connection to close. In your case it is: mysqli_close($db);
<!DOCTYPE html>
<html>
<head><title> SQL & PHP </title></head>
<body>
<?php
$db = mysqli_connect("localhost", "root", "password")
or die ("Non riesco a creare la connessione");
mysqli_select_db($db, "scuola") // see this line
or die ("Non trovo il DB");
$sql = "SELECT id_utente, nome_utente, password_utente, conta_pres FROM utenti WHERE conta_pres <> 0";
$ris = mysql_query($sql) or die ("Query fallita!");
echo "<TABLE><TR><TH>ID utente <TH> Nome utente <TH>Password<TH>Contatore visite</TR>";
while ($riga= mysql_fetch_array($ris))
{
echo ("<TR>");
echo "<TD>" . $riga["id_utente"];
echo "<TD>" . $riga["nome_utente"];
echo "<TD>" . $riga["password_utente"];
echo "<TD>" . $riga["conta_pres"];
}
mysqli_close($db); // see this line
?>
</body>
</html>
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.