Mysqli, SELECT FROM, php

本文关键字：php FROM SELECT Mysqli | 更新日期: 2023-09-27

我想做一个简单的SELECT用户名从数据库

$sql = "SELECT username
FROM users";
$select_sql = mysqli_query($conn, $sql);
$parse_sql = mysqli_fetch_array($select_sql);
var_dump($parse_sql);

但是它给了我这个与var_dump同时有多个条目。

array(2) {[0]=> string(0)" ["username"]=> string(0)"}

其他类似的查询工作正常

$sql = "SELECT username, password FROM users WHERE username ='$user'";
$select_sql = mysqli_query($conn, $sql);

I can't find what's wrong

使用while循环获取db_user

中的所有用户

$sql = "SELECT username
FROM db_user";
$select_sql = mysqli_query($conn, $sql);
while($parse_sql = mysqli_fetch_assoc($select_sql))
{
  $usernames[] = $parse_sql
}
var_dump($usernames);

mysqli_fetch_array只从结果集中获取单行。

考虑使用mysqli_fetch_all获取所有结果。

也可以只通过give

使用结果作为关联数组

mysqli_fetch_all($select_sql, MYSQLI_ASSOC);