I'm new to PHP and MYSQL. Is there a way to check number in length/values.
Example:
No = 0,
Yes = 1.
Code checks what number has int. If int is 0, website displays "Not Following" (echo "Not Following";). If int is 1, website displays "Following".
My code so far -
<?php
$servername = "localhost";
$username = "php_user";
$password = "password";
$dbname = "php_test";
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$conn->close();
?>
Currently your code just opens a connection with the database. You need to create a sql Select statement.
From there you can assign the values to variables and then use simple if statements to evaluate the data.
This link contains a tutorial on select statements: http://www.w3schools.com/sql/sql_select.asp
Related
Problem:
I want to get the MAX "SID" from my Database and add one. I handle the input via an Form that i submit through the HTTP Post Method. I get the current MAX "SID" from my database, then i put the value into an HTML input field and add one. For some reason this just works every other time. So the output i get is:
Try = 1
Try = 1
Try = 2
Try = 2
and so on. Would be nice if someone could point me in the right direction.
PHP get MAX(ID):
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "soccer";
$conn = mysqli_connect($servername, $username, $password, $dbname);
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
echo "Connected successfully";
$sql = "SELECT MAX(SID) FROM spieler";
$result = mysqli_query($conn, $sql);
if(mysqli_num_rows($result) > 0)
{
while($row = mysqli_fetch_assoc($result))
{
$lastID = $row["MAX(SID)"];
}
}
mysqli_close($conn);
PHP insert in database:
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "soccer";
$conn = mysqli_connect($servername, $username, $password, $dbname);
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
echo "Connected successfully";
?><br><?php
$sql = "INSERT INTO spieler VALUES ('$sid', '$name', '$verein',
'$position', '$einsaetze', '$startelf', '$tore',
'$torschuesse', '$eigentore', '$vorlagen', '$elfmeter',
'$verwandelt', '$gegentore', '$gelb',
'$rot', '$fouls', '$zweikampf', '$pass', '$note')";
if(mysqli_query($conn, $sql)){
echo "Success";
}else{
echo "Failed" . mysqli_error($conn);
}
mysqli_close($conn);
HTML & PHP Input Field:
<tr>
<td><input id="SID" name="SID" readonly value="<?php echo $lastID += 1;
?>"></td>
</tr>
Screenshot of the page:
The paragraph "Spieler ID:" is where I put the "SID" so that everytime the page loads the next free ID gets automatically loaded into the input field.
I want to get the MAX "SID" from my Database and add one
No. You don't. You really, really don't.
This is the XY Problem.
You can do it by running a system wide lock and a autonomous transaction. It would be a bit safer and a lot more efficient to maintain the last assigned value (or the next) as a state variable in a table rather than polling the assigned values. But this still ignores the fact that you going to great efforts to assign rules to what is a surrogate identifier and hence contains no meaningful data. It also massively limits the capacity and poses significant risks of both accidental and deliberate denial of service.
To further compound the error here, MySQL provides a mechanism to avoid all this pain out of the box using auto-increment ids.
While someone might argue that these are not portable, hence there may be merit in pursuing another solution, that clearly does not apply here, where your code has no other abstraction from the underlying DBMS.
I made a procedure in mySql. It looks like this.
I called this procedure from php.
After this call the table still remains empty and I do not know why.
Problems that I have checked:
variable names
connection
syntax (I think is the right syntax)
UPDATE: Php code
<?php
$servername = "localhost";
$username = "root";
$password = "";
$dbName = "shoppingcartdb";
// Create connection
$conn = new mysqli($servername, $username, $password, $dbName);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "INSERT INTO address (Address, PostalCode, City, County, Phone, Fax)
VALUES ('".$_POST["address"]."', '".$_POST["p_code"]."', '".$_POST["city_sector"]."', '".$_POST["county"]."', '".$_POST["phone"]."', '".$_POST["fax"]."')";
$conn->query($sql);
$sql = "CALL Insert_User('".$_POST["username"]."', '".$_POST["f_name"]."', '".$_POST["l_name"]."', '".$_POST["psw"]."', '".$_POST["email"]."')";
if(!$conn->query($sql))
echo "failed";
$conn->close();
?>
UPDATE: Procedure
Code ScreenShot
You have mixed up the input and local variables with session variables. #id_add is not the same as id_add, nor is #f_name the same ad f_name. Therefore you are trying to insert empty values into your table.
I cannot see on the screenshot if the delimiter was appropriatly set before and after the query. Pls check that.
Check the stored proc by testing it from phpmyadmin.
This question already has answers here:
Can I mix MySQL APIs in PHP?
(4 answers)
Closed 5 years ago.
here is my code, as you can see, I just wanna to connect mysql then insert a info field, but it seems not execute the next code after selected the db code, I am a newer in php, and it did not return an error, so I do not know where am I wrong..
<html>
<body>
Welcome <?php echo "show" ?><br>
Your email address is:
<?php
$servername = "localhost";
$username = "root";
$password = "123456";
// 创建连接
$conn = mysqli_connect($servername, $username, $password);
// 检测连接
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
echo "mysql successed connected.";
mysql_select_db("flowers", $conn) or die("database flowers failed".mysql_error()) ;
echo "database successed";
$sql="INSERT INTO flowers (username, password)
VALUES
('$_POST[name]','$_POST[email]')";
if (!mysql_query($sql,$conn))
{
die('Error: ' . mysql_error());
}
echo "1 record added";
mysql_close($conn);
?>
</body>
</html>
test demo info
and here is the db info:
dn info
I use ubuntu 16.04 apache2
So the main issue here is that you are using a combination of mysql_ and mysql functions. Note that mysql has been depreciated since PHP5 and has been completely removed in PHP7 so you should be using the newer mysqli or PDO. I personally use PDO, however have kept your code with mysqli.
<?php
$servername = "localhost";
$username = "root";
$password = "56lj0721";
// 创建连接
$conn = mysqli_connect($servername, $username, $password);
// 检测连接
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
echo "mysql successed connected.";
mysqli_select_db($conn,"flowers") or die("database flowers failed".mysqli_error()) ;
echo "database successed";
$sql="INSERT INTO flowers (username, password)
VALUES
('$_POST[name]','$_POST[email]')";
if (!mysqli_query($conn, $sql))
{
die('Error: ' . mysql_error());
}
echo "1 record added";
mysqli_close($conn);
?>
You should also really be using prepared statements to help prevent SQL Injection. You can read more here for mysqli.
It's also important to remember that you should be validating your $_POST['name'] and $_POST['email'] values as well, which I have not included.
If you want to read further about PDO, take a look here.
You have these two statements in your php code.
$conn = mysqli_connect($servername, $username, $password);
...
$conn = mysqli_connect($servername, $username, $password);
You should get rid of the second one if you must use the mysql_ interface to run your query.
You should also know, with respect, that only a fool uses the mysql_ interface in 2017. It has been deprecated for years, for reasons of cybersecurity, and is going away soon.
At the moment, I'm trying to store a value from a MySQL table as a variable in PHP, so running some basic tests to make sure that I can access the variable.
I've managed to store the varaible, which will either be a 1 or a 0 (1 = server is up and running, 0 = server down).
<?php
$servername = "localhost";
$username = "*****";
$password = "*****";
$dbname = "scicomservers";
// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "SELECT nccpm FROM web_servers WHERE time_checked='2016-02-16 11:44:17.212126'";
$nccpm = $conn->query($sql);
if($nccpm==1){
echo("NCCPM Server is running");
}
$conn->close();
?>
When I run this code, it reads in that $nccpm is 1, and it echos the statement, however, I get the error:
Notice: Object of class mysqli_result could not be converted to int in
/Applications/XAMPP/xamppfiles/htdocs/SciCom_admin_servers/files/connect2.php
on line 17
Line 17 being the if statement: "if($nccpm==1){".
I've had a look around on here, and I think this may be because it is trying to print an array of the answers, however it will only ever be one value that I will retrieve. The column of the DB is an int.
I was wondering, what would be a better way of coding this? It clearly isn't the best practice!
Thank you very much.
$sql = "SELECT nccpm FROM web_servers WHERE time_checked='2016-02-16 11:44:17.212126'";
$ncc = $conn->query($sql);
$nccpm = $conn->fetch_array($ncc);
if ($nccpm['nccpm'] == 1)
{
// Rest of script
}
You need to fetch your query or find how many rows are returned
I was wondering if anyone could shine a light on how to read from a database and pass it on to a sessions variable. I have tried with a product id and get but it did not work.
I'm looking for the basics on how to approach the issue.
I assume that you need to read from MySQL Database (for example).
First thing to do is reading PHP/MYSQL documentation.
http://www.w3schools.com/php/php_mysql_intro.asp
Second thing is to read about PHP Sessions.
http://www.w3schools.com/php/php_sessions.asp
And for example some code:
// Connect to MySQL Database and select all records from your_table
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$query = $conn->prepare("SELECT * FROM your_table");
$query->execute();
if($query == TRUE) {
// query success
}
To store information in $_SESSION variable you need to:
Call session_start(); before accessing this variable
$_SESSION['your_var'] = 'your_value';