PDO multiple named placeholders doesnt retrieve data

Question

The code I\'ve written so far works fine if there is only one named place holder for a prepared statement but if there are multiple conditions for a query, it doesn\'t retur

Answer 1

bindParam Requires a reference

The problem is caused by the way you bind parameters in the foreach loop.

foreach($bindings as $placeholder=>$bound){
    echo $placeholder . " - " . $bound."<br/>";
    $stmt->bindParam($placeholder, $bound);
}

bindParam requires a reference. It binds the variable, not the value, to the statement. Since the variable in a foreach loop is reset at the start of each iteration, only the last reference to $bound is left intact, and you end up binding all your placeholders to it.

That's why your code works when $query['where'] contains only one entry, but fails when it contains more than one.

You can solve the problem in 2 ways:

Pass by reference

foreach($bindings as $placeholder => &$bound) {  //pass $bound as a reference (&)
    $stmt->bindParam($placeholder, $bound);     // bind the variable to the statement
}

Pass by value

Use bindValue instead of bindParam:

foreach($bindings as $placeholder => $bound) {  
    $stmt->bindValue($placeholder, $bound);     // bind the value to the statement
}