Currently, I have the following structure in my PHP script, I would like one query to execute and if successful the next one should execute.
The following is my current code, but how can I add a simple
conditional that would allow the second query to execute after the
delete query?
<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "dbname";
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "DELETE FROM Table1" ;
$sql = " INSERT INTO Table1 (tbcolm, , tbcolm2, tbcolm3)
SELECT `column1`, `column2`,`column3` FROM Table3 ";
if ($conn->query($sql) === TRUE) {
echo "New record created successfully";
} else {
echo "Error: " . $sql . "<br>" . $conn->error;
}
$conn->close();
?>
You can use mysqli multi_query, as stated in PHP Manual:
https://secure.php.net/manual/en/mysqli.quickstart.multiple-statement.php
Be sure to add a ; at the end of your strings, and use the concatenating assignment operator (.=) on the second $sql variable.
It should look like this:
$sql = "DELETE FROM Table1;";
$sql .= "INSERT INTO Table1 (tbcolm, , tbcolm2, tbcolm3)
SELECT 'column1', 'column2','column3' FROM Table3;";
if ($mysqli->multi_query($sql)) {
/* success code here */
}
If the first argument fails, the next one won't be queried, as stated in:
https://www.php.net/manual/en/mysqli.multi-query.php
Related
I am trying to take the value of the topay column where torecieve equals to current session user id and use it to perform operation on the user table.
But it throws a syntax error
<?php
session_start();
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "bazze2";
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$merge = "SELECT topay FROM merge WHERE torecieve=$_SESSION[id]";
$sql = "UPDATE user SET topay2='10000000' WHERE 'id'=$merge";
if ($conn->query($sql) === TRUE) {
echo "Record updated successfully";
} else {
echo "Error updating record: " . $conn->error;
}
$conn->close();
?>
Use a prepared query, and use a join.
$sql = "UPDATE user AS u
JOIN merge AS m ON u.id = m.topay
SET u.topay2 = '10000000'
WHERE m.toreceive = ?";
$stmt = $conn->prepare($sql);
$stmt->bind_param('i', $_SESSION['id']);
if ($stmt->execute()) {
echo "Record updated successfully";
} else {
echo "Error updating record: " . $stmt->error;
}
I have very strange problem. I want to run mysql query as it is shown down below, but it's not working. Connection to database is successful, INSERT query is ok too, because when I run it directly in phpmyadmin Console it works, but it's not working here in PHP code.
Could you tell me what I'm missing?
$servername = "localhost";
$username = "admin";
$password = "admin123";
$dbname = "database1";
$conn = mysqli_connect($servername, $username, $password, $dbname);
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
$sql = "INSERT INTO last_visit (ip, lastvisit) VALUES ('123', '123')";
You need to run your $sql, because now your $sql is only a string, it does nothing.
Add this :
if ($conn->query($sql) === TRUE) {
echo "New record created successfully";
} else {
echo "Error: " . $sql . "<br>" . $conn->error;
}
My Code is :
//Catch
$myotp=$_GET["myotp"];
$rowid=$_GET["rowid"];
//Constructing the updat esql query
$update= "update order set dsotp ='$myotp' WHERE fsotp='$myotp' and id_order=$rowid";
//Excecuting the query
$res=mysqli_query($conn,$update);
It is working fine. But the problem is how to know from PHP code that it is updated the table?
You can check this way:
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "UPDATE MyGuests SET lastname='Doe' WHERE id=2";
if ($conn->query($sql) === TRUE) {
echo "Record updated successfully";
} else {
echo "Error updating record: " . $conn->error;
}
$conn->close();
Refer:https://www.w3schools.com/php/php_mysql_update.asp
mysqli_query returns TRUE or FALSE. and also the result set.
So, you can try this:
print_r($res);
PS: Also for the second part you can use mysqli_affected_rows($conn); to get the number of affected rows.
If you want to test if the query executed succesfully you should use the if statements provided above, however these do not check if there was any value updated. If you want that, you should use affected_rows.
http://php.net/manual/en/mysqli.affected-rows.php
A basic example would be this:
if($result = $mysqli->query($sql)){
var_dump($mysqli->affected_rows);
if($mysqli->affected_rows == 1){
return TRUE;
} else{
return FALSE;
}
}
I have problem with MySQL database, I can't insert the information into the table. My php code seems to work, but when I run it nothing happens.
<?php
$servername = "localhost";
$fname = "fname";
$lname = "lname";
$klas = "klas";
$nomer = "nomer";
$file = "dom";
$dbname = "homeworks";
$conn = new mysqli($servername, $fname, $lname,$klas,$file,$dbname);
$sql = "INSERT INTO student (fname, lname,klas,file)
VALUES ($servername, $fname, $lname,$klas,$file,)";
?>
You have three main problems in your code:
You're still not connected to the database
Only constructing and not executing
Having not matched parameters in the insert values
Solution :
1. Make a connection first
$conn = new mysqli($servername, $username, $password, $dbname);
The Parameter $servername, $username, $password, $dbname is obviously your hostname, Database Username, Password and the Database name
You should not have your table name or column names in the connection parameters
2. Construct the parameters which matches the coloumn name and variables correctly
$sql = "INSERT INTO student (fname, lname,klas,file)
VALUES ($fname, $lname,$klas,$file)";
3. Execute Your Query :
if ($conn->query($sql) === TRUE) {
echo "New record created successfully";
} else {
echo "Error: " . $sql . "<br>" . $conn->error;
}
Note :
Also it's good practice to close your connection once you are done
$conn->close();
So, you should be having something like this
<?php
$servername = "localhost";
$username = "YourDBUsername";
$password = "YourDBPassword";
$fname = "fname";
$lname = "lname";
$klas = "klas";
$nomer = "nomer";
$file = "dom";
$dbname = "homeworks"; //Hope you will have your db name here
$conn = new mysqli($servername, $username, $password, $dbname);
$sql = "
INSERT INTO student (fname, lname,klas,file) VALUES
('$fname'
,'$lname'
,'$klas'
,'$file');
";
if ($conn->query($sql) === TRUE) {
echo "New record inserted successfully";
} else {
echo "Error: " . $sql . "<br>" . $conn->error;
}
$conn->close();
Advice :
Always use prepared statements else clean your inputs before you insert.
Your connection should look something like this. link
<?php
//change the data into your connection data
$conn = mysqli_connect("localhost","my_user","my_password","my_db");
// Check connection
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
?>
You made your query but didn't execute it.
if (mysqli_query($conn, $sql)) {
echo 'records created successfully<br>';
} else {
echo $sql . '"<br>"' . mysqli_error($conn);
}
I have a very simple bit of code to insert data into database.
It doesn't work. I do not get any error except cannot insert. I could connect to the database so that is not the issue.
The database has 3 fields, emailadd is the 2nd field. The other 2 are auto increment id and creation date, so also a field that on add, it will add current timestamp.
$inquiry = "INSERT INTO subscribe (emailadd) VALUES ('$myemail')";
$res = mysql_query($inquiry) or die("cannot insert");
$inquiry = "INSERT INTO `subscribe` (`emailadd`) VALUES ('$myemail')";
$res = mysql_query($inquiry,$con) or die('Not Inserted : ' . mysql_error());
Some time we need $con variable to identify the database connection, let see more check here
the mysql_query is deprecated, you need to use mysqli like so :
<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "UPDATE MyGuests SET lastname='Doe' WHERE id=2";
if ($conn->query($sql) === TRUE) {
echo "Record updated successfully";
} else {
echo "Error updating record: " . $conn->error;
}
$conn->close();
?>