I have a script and connects to a database, then inserts data into a database. However I am having an issue fetching the data.
Here is the error message I get: Fatal error: Call to a member function fetchAll() on boolean in C:\xampp\htdocs\projects\forms\db.php on line 24
What am I doing wrong?
Here is the script
<?php
//This script provides connection to the database//
//Connect
$user="root";
$pass="";
try {
$connection = new PDO('mysql:host=localhost;dbname=thetest', $user, $pass);
} catch (Exception $e) {
print "Error!: " . $e->getMessage() . "<br/>";
die();
}
//Insert
try {
$stmt = $connection->prepare("INSERT INTO `users`(`name`, `lastname`, `age`) VALUES(?,?,?)");
$stmt->execute(array("Dave", "Smithers", "22"));
} catch (Exception $e) {
echo "Error!: " . $e->getMessage() . "<br/>";
die();
}
//Fetch
try {
$stmt = $connection->prepare("SELECT `name` FROM `users` WHERE `lastname` = 'Smithers'");
$result = $stmt->execute();
$user = $result->fetchAll();
print_r($user);
} catch (Exception $e) {
echo "Error!: " . $e->getMessage() . "<br/>";
}
?>
$stmt->execute() returns a boolean indicating success/failure.
Instead, use this:
$stmt->execute();
$result = $stmt->fetchAll();
Related
I'm trying to fetch data from a SQL Server database. After debugging, I could figure there's something wrong with the function.
Here's the code:
db.php
class Db{
public static function getConnection() {
$server='xxx';
$database='xxx';
$user='xxx';
$password='xxx';
$dsn="dblib:host=" . $server . ";dbname=" . $database;
try {
$conn = new PDO($dsn, $user, $password);
}
catch (PDOException $e) {
echo 'SQL SERVER CONNECTION ERROR: ' . $e->getMessage();
}
return $conn;
}
}
functions.php
class Functions {
function getAcademicYear() {
$db = new Db();
$conn = $db->getConnection();
$conn->beginTransaction();
$sql = "SELECT academicYear FROM AcademicYear ORDER BY academicYearId DESC LIMIT 5";
$stmt = $conn->prepare($sql);
if ($stmt->execute()) {
$result = $stmt->fetchAll(PDO::FETCH_ASSOC);
$conn->commit();
echo $result;
} else {
$conn->rollback();
echo "false";
}
}
}
The function is returning false. Can you please review it and point out any mistakes?
Please help with this difficult to understand bug: php always execute sql update inside IF with $_POST in condition.
When condition is false: the code i) not executes the echo command, but ii) it still executes the sql command
if ($_POST["scanned_set"] != "saved") {
try {
$conn = new PDO("mysql:host=$servername;dbname=abc", $username, $password);
// set the PDO error mode to exception
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
echo "Connected successfully";
// Update
$sql = "UPDATE `id_scan` SET `scan_count` = 10 WHERE `id_scan`.`id` = 1";
// use exec() because no results are returned
$conn->exec($sql);
} catch(PDOException $e) {
echo "Connection failed: " . $e->getMessage();
}
$conn = null;
}
and the strange thing is that, if I try the iF condition with "IF (1 ==2)" then code works well. In other words, it does not execute the sql.
The full code
<html>
<body>
<?php
$servername = "localhost";
$username = "reviinve_vchain";
$password = "";
var_dump($_POST["scanned_set"]);
try {
$conn = new PDO("mysql:host=$servername;dbname=reviinve_vchain", $username, $password);
// set the PDO error mode to exception
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
echo "Connected successfully";
// Retrieve data from db
$sql = "SELECT * FROM `id_scan` WHERE `id` = 1";
foreach ($conn->query($sql) as $row) {
echo "print scan number after retrieving statement ".$row['scan_count'] . "\t";
// print $row['color'] . "\t";
$count_update = $row['scan_count'] + 1;
}
}
catch(PDOException $e){
echo "Connection failed: " . $e->getMessage();
}
$conn = null;
if ($_POST["scanned_set"] != "saved") {
try {
$conn = new PDO("mysql:host=$servername;dbname=reviinve_vchain", $username, $password);
// set the PDO error mode to exception
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
echo "Connected successfully";
// Update count number to db
echo 'new count number' . $count_update;
$sql = "UPDATE `id_scan` SET `scan_count` = $count_update WHERE `id_scan`.`id` = 1";
// use exec() because no results are returned
$conn->exec($sql);
}
catch(PDOException $e) {
echo "Connection failed: " . $e->getMessage();
}
$conn = null;
}
?>
</body>
</html>
Try scrubbing your request variable first:
$do_update = !(trim(strtolower($_REQUEST["scanned_set"])) == "saved")
if ($do_update) {
try {
$conn = new PDO("mysql:host=$servername;dbname=abc", $username, $password);
// set the PDO error mode to exception
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
echo "Connected successfully";
// Update
$sql = "UPDATE `id_scan` SET `scan_count` = 10 WHERE `id_scan`.`id` = 1";
// use exec() because no results are returned
$conn->exec($sql);
} catch(PDOException $e) {
echo "Connection failed: " . $e->getMessage();
}
$conn = null;
}
This question already has answers here:
How to get last inserted inserted row id from PDO
(2 answers)
Closed 5 years ago.
in this code i have to insert some value in DB, then i have to take last id inserted in DB and sent it to another page to show the value of that id row. here is my code for insert data in DB :
try {
$con = new PDO("mysql:host=localhost;dbname=resume", "root", "");
$con->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$sql_basic = "INSERT INTO user_basic_info (first_name,last_name,address,profile_pic,resume_file)
VALUES ('$FirstName','$LastName','$Address','$pic_destination','$resume_destination')";
$con->exec($sql_basic);
$last_id = $con->$lastInsertId();
} catch (PDOException $e) {
echo $sql_basic . "<br>" . $e->getMessage() . "<br>";
}
$con = null;
header('Location: DB-Read.php?id=' . $last_id);
in another php page i have to take $last_id and use it. here is my code:
try {
$user_id = $id;
$conn = new PDO("mysql:host=localhost;dbname=resume", "root", "");
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$stmt = $conn->prepare("SELECT first_name FROM user_basic_info where user_id = ".$user_id);
$stmt->execute();
$result = $stmt->setFetchMode(PDO::FETCH_ASSOC);
echo "this is username: " . $result;
} catch (PDOException $e) {
echo "Error: " . $e->getMessage();
}
$conn = null;
header('Location: show-edit.php?id=' . $last_id);
first of all $lastInsertId() not working !!
after that, is my way true to take $last_id from first page ?
lastInsertId is a method of the PDO object. You need to call $conn->lastInsertId();.
Your given syntax $conn->$lastInsertId(); is valid, however, it does not do, what you are expecting. It considers $lastInsertId to be a variable containing the method name to be called. The following example would work as well:
$method_name = 'lastInsertId';
$conn->$method_name();
Be aware that your solution enables anyone to fetch any row of your table. Consider using sessions.
TRY THIS:
use session:
try {
$con = new PDO("mysql:host=localhost;dbname=resume", "root", "");
$con->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$sql_basic = "INSERT INTO user_basic_info (first_name,last_name,address,profile_pic,resume_file)
VALUES ('$FirstName','$LastName','$Address','$pic_destination','$resume_destination')";
$con->exec($sql_basic);
$_SESSION['id'] = $con->lastInsertId(); //it's a method
} catch (PDOException $e) {
echo $sql_basic . "<br>" . $e->getMessage() . "<br>";
$con = null;
header('Location: DB-Read.php?id=' . $last_id);
Now use this code
try {
$user_id = $_SESSION['id'];
$conn = new PDO("mysql:host=localhost;dbname=resume", "root", "");
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$stmt = $conn->prepare("SELECT first_name FROM user_basic_info where user_id = ".$user_id);
$stmt->execute();
$result = $stmt->setFetchMode(PDO::FETCH_ASSOC);
echo "this is username: " . $result;
} catch (PDOException $e) {
echo "Error: " . $e->getMessage();
}
$conn = null;
header('Location: show-edit.php?id=' . $last_id);
I previously used mysqli and now i would like to use PDO instead but I did not echo any result from my database. I have read so many articles about PDO tutorial but they teach different things. I tried to pick piece by piece and came up with this code, but i did not echo any result from my database or throw any error.
try{
$stmt = $conn->query("SELECT * FROM memberpost ORDER BY poststart DESC LIMIT $start_from,$num_rec_per_page");
$stmt->setFetchMode(PDO::FETCH_ASSOC);
$row = $stmt->fetch();
if(count($row)>0){
while($row = $stmt->fetch()) {
echo $row['title']."<br>";
}
}
else{
echo "NO result found";
}
} catch(PDOException $e) {
echo 'ERROR: ' . $e->getMessage();
}
Here is my database connect code:
try {
$conn = new PDO('mysql:host=localhost;dbname=mydatabase;charset=utf8', $username, $password); //new PDO
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch(PDOException $e) {
echo 'ERROR: ' . $e->getMessage();
}
Edit your database connection code to this:
<?php
$dsn = 'mysql:dbname=testdb;host=127.0.0.1';
$user = 'dbuser';
$password = 'dbpass';
try {
$dbh = new PDO($dsn, $user, $password);
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch (PDOException $e) {
echo 'Connection failed: ' . $e->getMessage();
}
?>
And try this code in your .php file :
$sth = $conn->prepare(SELECT * FROM memberpost)
$sth->execute();
$red = $sth->fetchAll();
print_r($red);
I found this on the internet, it might help:
// defining query
$sql = 'SELECT name, surname, zip FROM table';
// showing results
foreach($db->query($sql) as $row){
echo $row['name']. '<br>';
echo $row['surname']. '<br>';
echo $row['zip']. '<br>';
}
Source (ita): http://www.mrwebmaster.it/php/guida-utilizzo-pdo_7594_4.html
I want to delete a row from a table using php pdo.I am using the following code,
$dsn = 'mysql:host=127.0.0.1;dbname=as1';
$user = 'root';
$password = '';
try {
// Connect and create the PDO object
$pdo = new PDO($dsn, $user, $password);
$pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
}
catch(PDOException $e) {
echo 'Database connection failed - ';
echo $e->getMessage();
exit;
}
$sql1="DELETE FROM photo WHERE id=?";
$q1=array($result);
try {
$stmt1 = $pdo->prepare($sql1);
$stmt1->execute($q1);
$stmt1->setFetchMode(PDO::FETCH_BOTH);
$result1= $stmt1->fetchColumn();
}
catch (PDOException $e) {
die("Failed to run query: " . $e->getMessage());
}
But my datas in a table are not deleting ...It shows failed to run query..
You did not provide a value for ?
$stmt1->execute($q); // Where is $q defined?
Should be something like
$q=array(1);
$stmt1->execute($q);