how do they return same result?

Question

Here, $user_id is single quoted:

$select = $conn->query("SELECT firstname,lastname FROM users WHERE user_id = '$user_id'");
$row = $select->fetch_assoc();
    print_r($row);

Here, $user_id is not single quoted

$select = $conn->query("SELECT firstname,lastname FROM users WHERE user_id = $user_id");
$row = $select->fetch_assoc();
    print_r($row);

If $user_id = 1, does '1' == 1?? Both return associative array of $user_id = 1.

because, MySQL is forgiving when it comes to quoted integers. Had that variable been a string, it would be a different story. This being *"the short answer"*. So now you know. — Funk Forty Niner, May 25 '16 at 19:02

score 0 · Answer 1 · answered May 25 '16 at 19:11

0

For your use case, yes, '1' == 1.

From the docs:

To cast a string to a numeric value in numeric context, you normally do not have to do anything other than to use the string value as though it were a number:
mysql> SELECT 1+'1';
       -> 2

answered May 25 '16 at 19:11

cyberbit

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how do they return same result?

1 Answers1