The handling of errors by this function is controlled by the attribute PDO::ATTR_ERRMODE.

Use the following to make it throw an exception:
<?php
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
?>

Trying to pass like second argument PDO::FETCH_ASSOC it still work.

So passing FETCH TYPE like argument seems work.

This save you from something like:

<?php
$result = $stmt->setFetchMode(PDO::FETCH_NUM);
?>

Example:
<?php
$res = $db->query('SELECT * FROM `mytable` WHERE true', PDO::FETCH_ASSOC);

?>

After a lot of hours working with DataLink on Oracle->MySQL and PDO we (me and Adriano Rodrigues, that solve it) discover that PDO (and oci too) need the attribute AUTOCOMMIT set to FALSE to work correctly with.
There's  3 ways to set autocommit to false: On constructor, setting the atribute after construct and before query data or initiating a Transaction (that turns off autocommit mode)

The examples:
<?php
// First way - On PDO Constructor
$options = array(PDO::ATTR_AUTOCOMMIT=>FALSE);

$pdo = new PDO($dsn,$user,$pass,$options);

// now we are ready to query DataLinks

?>

<?php 
// Second Way - Before create statements
$pdo = new PDO($dsn,$user,$pass);

$pdo->setAttribute(PDO::ATTR_AUTOCOMMIT,FALSE);
// or
$pdo->beginTransaction();

// now we are ready to query DataLinks
?>

To use DataLinks on oci just use OCI_DEFAULT on oci_execute() function;

> When query() fails, the boolean false is returned. 

I think that is "Silent Mode".
If that set attribute ErrorMode "Exception Mode"
then that throw PDOException.
 $pdoObj = new PDO( $dsn, $user, $pass );
 $pdoObj->setAttribute("PDO::ATTR_ERRMODE", PDO::ERRMODE_EXCEPTION);

I would like to mention fetching rows from SQL query using PDO:

<?php

$dbh = new PDO('mysql:host=localhost;dbname=test', $user, $pass);

// use the connection here
$sth = $dbh->query('SELECT * FROM countries');

// fetch all rows into array, by default PDO::FETCH_BOTH is used
$rows = $stm->fetchAll();

// iterate over array by index and by name
foreach($rows as $row) {

    printf("$row[0] $row[1] $row[2]\n");
    printf("$row['id'] $row['name'] $row['population']\n");

}
?>

When you make a wraper for PDO:query, you must define the method like this:

public function query( string $sql,  ?int $fetchMode = null, mixed ...$fetchModeArgs) : \PDOStatement|false
    
if you delete one of the parameters or use one of the oficials parameters you get a Fatal error