How do I display content with PDO based on num_rows? - php

Question

Apparently, the num_rows property does not work in PDO as it would with mysqli.
Normally, with mysqli, my code would look like this:
<?php
$conn = new mysqli('127.0.0.1','root','mypassword','mydbname');
if($conn->connect_errno){
die("Sorry, could not connect.");
}
$id = 1;
$qry = "SELECT * FROM customers WHERE id = ?";
$getCustomers = $conn->prepare($qry);
$getCustomers->bind_param("i",$id);
$getCustomers->execute();
$result = $getCustomers->get_result();
$count = $result->num_rows;
if($count == 0){
echo "Sorry, there are no results";
}else{
while($row = $result->fetch_object()){
echo $row->id;
echo $row->fname;
echo $row->lname;
echo $row->entry_date;
}
}
?>
How do I create the equivalent with PDO? Here is what I have tried so far:
<?php
try{
$conn = new PDO('mysql:host=127.0.0.1;dbname=mydbname','root','mypassword');
}catch(PDOException $e){
echo $e;
}
$id = 1;
$qry = $conn->prepare("SELECT * FROM customers WHERE id = :id");
$qry->execute([':id'=>$id]);
$rows = $qry->fetchAll(PDO::FETCH_OBJ);
$count = count($rows);
if($count == 0){
echo "Sorry, there are no results for your criteria";
}else{
for($i = 0; $i < $count; $i++){
echo $rows->fname;
}
}
?>

Answer 1

Yeah isn't PDO great ;p no need to count rows when you have already got them.
To loop over your result as you have an array.
Change:
for ($i = 0; $i < $count; $i++){
echo $rows->fname;
}
To:
for ($i = 0; $i < $count; $i++){
echo $rows[$i]->fname;
}
Or better just use a foreach.
foreach ($rows as $row) {
echo $row->fname;
}

Answer 2

The statement
fetchAll(PDO::FETCH_OBJ) returns an array containing all of the result set rows as described here. To get the size of the array use sizeof($count). That should give you the size of the array.

Answer 3

To answer your question specifically. You can use rowCount() to retrieve the number of rows in a result:
$qry = $conn->prepare("SELECT * FROM customers WHERE id = :id");
$qry->execute([':id'=>$id]);
$count = $qry->rowCount();
$rows = $qry->fetchAll(PDO::FETCH_ASSOC); //my personal preference
for($i=0; $i < $count; $i++) {
echo $rows[$i]['fname'];
}
To more closely replicate your mysqli code:
while($row = $qry->fetch(PDO::FETCH_OBJ) {
echo $row->fname;
}
Of course, you should always check $conn->errorCode() after each database execution to ensure something go sideways on you.
UPDATE:
As Lawrence points out, rowCount() does not work with MS SQL Server. An alternative in that case is to use fetchAll() and count().