PDO Count & Loop Optimization - php

Question

Information
I am starting to notice a trend in my coding habits that I wonder if there is a better way to do it.
Problem
For the sake of an example, lets pretend I have a table that may have data in it, ideally I want to loop through the data if there is any, if not display an error message.
Current Solution
function countResults($type){
$STH = $this->database->prepare('SELECT COUNT(*) FROM table WHERE type = :type');
$STH->execute(array(':type' => $type));
return $STH->fetchColumn();
}
if($class->countResults("1") != 0){
$STH = $this->database->prepare('SELECT * FROM table WHERE type = :type ');
$STH->execute(array(':type' => $type));
while($row = $STH->fetch(PDO::FETCH_ASSOC)){
echo "Row Name:".$row['name']."<br />";
}
} else {
echo "None found";
}
Attempts Made
I have tried a solution of cutting this down by storing $STH->fetch(PDO::FETCH_ASSOC) into a variable then using if(!empty($var)){// loop code}; but it doesn't allow me to loop out the data correctly.
Conclusion
I understand this isn't a ground breaking bug that I am struggling to fix urgently, but I feel as if this is becoming a bad habit and there's a little nag in my mind that there is a smarter solution to this which I would love to learn before it turns into a habit!
Feel free to ask questions if needed, Thank you.

Answer 1

Your approach is rather illogical than wrong. All you need is common sense.
Imagine you're going to buy a six-pack. Are you getting cash from the pocket in two actions, or one? Are you really do like this:
Reach into pocket, only to feel the money. There are some. Okay.
Take the hand back and then reach again - for the money this time.
Why not to reach just once, and buy your beer if you get enough, or say sorry if not?
$STH = $this->database->prepare('SELECT * FROM table WHERE type = :type ');
$STH->execute(array(':type' => $type));
$data = $STH->fetchAll();
if ($data)
{
foreach($data as $row)
{
echo "Row Name:".$row['name']."<br />";
}
} else {
echo "None found";
}

Answer 2

There are two options I would use. Option one, similar to what you are doing:
$STH = $this->database->prepare('SELECT * FROM table WHERE type = :type ');
$STH->execute(array(':type' => $type));
if ($STH->rowCount() > 0)
while($row = $STH->fetch(PDO::FETCH_ASSOC)){
echo "Row Name:".$row['name']."<br />";
}
} else {
echo "None found";
}
Note that the PHP manual for PDOStatement::rowCount() warns that this might not return the number of rows from a SELECT query on all database types.
What I actually do, is separating the SQL logic from the display, usually by using the template engine Smarty. In that case you have two separate files:
PHP:
$STH = $this->database->prepare('SELECT * FROM table WHERE type = :type ');
$STH->execute(array(':type' => $type));
$objects = $STH->fetchAll();
$template->assign("objects", $objects); // this assigns the array with all returned rows to the template.
Smarty Template:
{foreach from=$objects item=object}
Row Name: {$object.name}<br />
{foreachelse}
None found
{/foreach}
This will basically output the same, with separated logic.
Both methods will prevent doing unnessecary queries or doing the same query twice.

Answer 3

I would do it this way, if anyone sees anything wrong please point it out:
I prefer foreach because I can access the field name
I like to get used to use count() instead of rowCount() because rowCount() can return 2 for an updated row, even if this query is a select, I feel like I could get used to it and have mistakes.
I like to check if it returns false to debug. Normally I do a one-liner for this, so I can comment it out or remove it easily on production
function myQuery(){
$STH = $this->database->prepare('SELECT * FROM table WHERE type = :type ');
$STH->execute(array(':type' => $type));
$data = $STH->fetchAll(PDO::FETCH_ASSOC);
if($data === false) return "SQL query Error"; // or a method/function that returns the actual error code/message";
if($data){
foreach($data as $k => $v) echo "$k: $v<br>"; // I actually prefer to return the array $data and handle the info elsewhere
} else {
"None Found";
}
}