dongqiang8683 2015-07-02 14:32
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使用PDO绑定SOMETIMES null值

There is only one record in my database, and the "action_taken" column is set to NULL. How the hell do I get PDO to find it???

If I type the query directly into SQL it works as expected.

Note: This is just a test script to illustrate my problem. Most the time the value passed will be a string, but occasionally the value will be NULL.

include ('include/mysql.php');

$sql = 'SELECT * FROM returns WHERE action_taken = :action';
$sth = $dbh->prepare($sql);
$param = null;
$sth->bindValue(':action', $param, PDO::PARAM_STR);
$sth->execute();
if ($sth->rowCount())
    {
    echo 'FOUND YOU!';
    }
else
    {
    echo 'NOOOO :(';
    }
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1条回答 默认 最新

  • dqppv86022 2015-07-02 15:21
    关注

    Basically, you can't say "equal to null". It always has to be IS null:

    $sql = 'SELECT * FROM returns WHERE action_taken IS :action';
    

    You'd be better off not using NULL at all, if at all possible.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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