php - MySQL/PHP INSERT MySQL 问题？

Question

如何将两行插入到两个不同的表中。我好像没听懂？

这是下面的代码。

// tag is not there, so insert a new instance
  $mysqli = new mysqli("localhost", "root", "", "sitename");
  $clean_url = mysqli_real_escape_string($mysqli, $page);
  $dbc = mysqli_query($mysqli,"INSERT INTO q_tags (tag_id, users_q_id) VALUES ('$tag_num', '$page')");
  $dbc .= mysqli_query($mysqli,"INSERT INTO tags (tag) VALUES ('$tag')");

     echo "$tag has been entered";

if (!$dbc) {
        // There was an error...do something about it here...
        print mysqli_error($mysqli);
}

Answer 1

. 运算符用于附加字符串。您正在尝试使用此运算符附加 bool 值(mysqli_query 的结果)，这意味着当您稍后检查它的值时，它不会保留您期望的值。试试这个:

// tag is not there, so insert a new instance
$mysqli = new mysqli("localhost", "root", "", "sitename");
$clean_url = mysqli_real_escape_string($mysqli, $page);

$query1 = "INSERT INTO q_tags (tag_id, users_q_id) VALUES ('$tag_num', '$page')";
$query2 = "INSERT INTO tags (tag) VALUES ('$tag')":

if (!mysqli_query($mysqli, $query1)) {
    print mysqli_error($mysqli);
    return;  // or exit if this isn't in a function call
}

if (!mysqli_query($mysqli, $query2)) {
    print mysqli_error($mysqli);
    return;  // or exit if this isn't in a function call
}

echo "$tag has been entered";