MySQL fetch_assoc() shows 1 less result

问题

i have a table like below:

hub dep
A B
A C
B D
B E
B F
E G

i use mysql select to get query and my code is like below:

$sql         = "SELECT dep FROM handd WHERE hub='B'";
        $result      = $conn->query( $sql );
        $row         = $result->fetch_assoc();

        while($row = $result->fetch_assoc()) {
    echo "id: " . $row["dep"]."<br>";
}

but it just gives me result like below:

id: E
id: F

and i am wondering where is D?

回答1:

 $row         = $result->fetch_assoc();

This line stores the result of 'B D'. It actually should be:

    $sql         = "SELECT dep FROM handd WHERE hub='B'";
    $result      = $conn->query( $sql );

    while($row = $result->fetch_assoc()) {
        echo "id: " . $row["dep"]."<br>";
    }

来源：https://stackoverflow.com/questions/39943290/mysql-fetch-assoc-shows-1-less-result