PHP PDO MySQL No Exception or Error

Question

I've got the following script that uses PDO.

    $db = new PDO("mysql:host=$hostname;dbname=$database", $username, $password);

    $sql    = "BEGIN;\n".
              "INSERT INTO exp_ws_gk_text (WGT_PRG_CODE, WGT_TEXT)\n".
              "    VALUES('".$_POST['prg_code']."', ".$db->quote($_POST['text']).");\n" .
              "SELECT @Lid:=LAST_INSERT_ID();\n" .
              "INSERT INTO exp_ws_gk_state (WGS_STATE, WGS_TYPE, WGS_WGT_RID)\n".
              "    VALUES('".$_POST['state']."', ".$_POST['type'].", @Lid);\n".
              "SELECT a.wgt_prg_code prg_code, b.wgs_state state, b.wgs_type type, a.wgt_rid id, a.wgt_text text\n".
              "    FROM exp_ws_gk_text a\n".
              "    JOIN exp_ws_gk_state b ON b.wgs_wgt_rid = a.wgt_rid\n".
              "    WHERE b.wgs_wgt_rid = @Lid ORDER BY a.wgt_prg_code;\n".
              "COMMIT;\n";

$fp = fopen("/var/tmp/save_gatekeeper.txt", "a");
fwrite($fp, "SQL:". $sql."\n");

    try {
        $res = $db->prepare($sql);
        $res->execute();
        $error = $db->errorInfo();

fwrite($fp, "ErrorInfo:".print_r($error, true)."\n\n");
fwrite($fp, "Row:      ".print_r($res->fetch(PDO::FETCH_ASSOC), true)."\n\n");
fwrite($fp, "Row2:     ".print_r($res->fetch(PDO::FETCH_LAZY),true)."\n\n");

    }
    catch (PDOException $e) {

fwrite($fp, "ExceptionInfo:".print_r($e, true)."\n\n");

    }    

fclose($fp);

    echo json_encode($res->fetch(PDO::FETCH_ASSOC););

This is what the log produced:

SQL:BEGIN;
INSERT INTO exp_ws_gk_text (WGT_PRG_CODE, WGT_TEXT)
    VALUES('EDS', '[h3]IMPORTANT INFORMATION[/h3][p]This is a test gatekeeper for [b]Eddie\'s[/b] Classroom Course[/p]');
SELECT @Lid:=LAST_INSERT_ID();
INSERT INTO exp_ws_gk_state (WGS_STATE, WGS_TYPE, WGS_WGT_RID)
    VALUES('AL', 1, @Lid);
SELECT a.wgt_prg_code prg_code, b.wgs_state state, b.wgs_type type, a.wgt_rid id, a.wgt_text text
    FROM exp_ws_gk_text a
    JOIN exp_ws_gk_state b ON b.wgs_wgt_rid = a.wgt_rid
    WHERE b.wgs_wgt_rid = @Lid ORDER BY a.wgt_prg_code;
COMMIT;

ErrorInfo:Array
(
    [0] => 00000
)


Row:      

Row2:     

I'm not sure why it isn't reporting any kind of error or exception. This is the first time I'm using PDO. I converted from using the older mysql calls.

Can someone help out here?

I'm expecting the results from the last select to be sent back, all I get is "false";

Answer 1

Since you're using a prepared statement with multiple queries, you need to use emulated prepared statements. Refer to PDO support for multiple queries (PDO_MYSQL, PDO_MYSQLND)

$db->setAttribute(PDO::ATTR_EMULATE_PREPARES, 1);

Otherwise, I believe the only thing you are executing is BEGIN;

---

In my personal opinion, I think this is bad practice to put multiple queries into one PDO statement. You should consider using a transaction with PDO and multiple statements which allows you to more easily figure which query is causing issues and rollback if an error occurs.

---

Secondly, you are using prepared statements but are still not protecting yourself from SQL injections. Don't use $_POST in the prepare(). You are supposed to bind those after you prepare the statement.

Answer 2

Cheers, we solved this in chat.

You're mixing multiple types of statements. You need to separate out your queries into two separate queries; one with the INSERT with $res->query , and then validate the response, and then another with the SELECT using $res->fetch() or $res->fetchAll()