在php中使用PDO时，从mysql数据库读取数组时出现问题

Question

I have the following code set to read and output a specific row from a database based on the criteria in the query statement below. When I try to log the output in console, however, I am only able to get one value and while it DOES exist in the database (as a key attribute), it is from the first row every time. I am not getting a row that matches the SQL criteria. Any ideas?

function getLoginInfo($email,$password){
    global $db_user, $db_password, $db_host, $db_name;

    if (isValidLogin($email,$password)){
        $dbconn = connectToDB($db_user, $db_password, $db_host, $db_name);
        $userInfoQuery = $dbconn->prepare("Select * from (Users as U inner join RegisteredUsers as R on U.UID = R.UID) where email = :email");
        $userInfoQuery->execute(array(":email"=> 'derp@gmail.com'));
        $results = $userInfoQuery->fetch(PDO::FETCH_ASSOC);     
        echo $results; //will return data in the form ["col1"=>rowdata,"col2"=>rowdata,..."colX"=>rowdata]
        }
    else{
        return false;
    }
}

Answer 1

You need to use a loop to fetch all the rows returned by your query:

while( $results = $userInfoQuery->fetch(PDO::FETCH_ASSOC) ) { 
    echo $results;
}

The documentation for the PDOStatement::fetch function says that the function "Fetches the next row from a result set", so it only returns one row. If the PDOStatement::fetchAll functions that will return the full result set.