| Re: PDO - Cannot retrieve warnings with emulated prepares disabled [message #183519 is a reply to message #183511] |
Tue, 29 October 2013 20:09   |
Jerry Stuckle
Messages: 2598
Registered: September 2010
Karma:
|
Senior Member |
|
|
On 10/29/2013 11:22 AM, Thomas Mlynarczyk wrote:
> Jerry Stuckle schrieb:
>
>> I could be wrong, but from my experience, the mysql driver has never
>> supported prepared statements, while the mysqli driver has always
>> supported them. This is why PDO has to emulate the prepared statements.
>
> This is what PDO tells me about the driver being used:
> PDO::ATTR_CLIENT_VERSION => mysqlnd 5.0.10 - 20111026
>
Ok, so you're using MySQL's driver for PHP 5.4+. That's good; it
supports everything.
>> If you disable emulation with a mysql connection, I would expect
>> errors in the execution. What is the return value from your prepare()
>> and execute() calls?
>
> Prepare() returns a PDOStatement object and execute returns true.
>
Yea, I though about the prepare() - if it didn't return a PDOStatement
object your execute() call would get a fatal exception ($stmt not an
object). But I'm surprised that the execute() call returns true.
> Everything works fine with PDO::ATTR_EMULATE_PREPARES == false (except
> for the issue with SHOW WARNINGS) and consistent with the assumption
> that prepared statements are indeed supported.
>
> $pdo->prepare( 'invalid' ) will return false; with emulated prepares it
> will return a PDOStatement object -- both as expected.
>
That part is as it should be.
> With emulated prepares,
>
> $stmt = $pdo->prepare( 'SELECT * FROM mytable LIMIT ?' );
> $stmt->execute( [ 4 ] );
>
> will give me a syntax error complaining about "LIMIT '4'", whereas with
> PDO::ATTR_EMULATE_PREPARES == false the query works fine (proving that
> the ? placeholder was indeed replaced with (int) 4 instead of (string) '4'.
>
> Greetings,
> Thomas
>
If anything, I would have expected the opposite to be true - works with
emulation but not with PDO::ATTR_EMULATE_PREPARES == false, but that's
only because I think PDO has a bit more flexibility in preparing
statements. I could be wrong, though.
Do you get a result from the 'Select 5 + "Five"'? If so, what is it?
Also, what happens if you try "Select 5 + 'Five'"? (note different quoting).
I'm beginning to think you've found a bug in the PDO extension, but I'm
not sure (yet).
--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex(at)attglobal(dot)net
==================
|
|
|
|
Calendar
Search
Help
Members
Register
Login
Home
]