Question

以下是我正在尝试创建数据库连接的代码段。请在我提到的代码中查看下面的注释，问题恰好发生在哪里。此外，我还提到了一个工作正常的连接代码。

请告诉我如何拨打我的dbconfig.php，以便它的行为类似于导致连接成功的代码。

由于

<?php

//Including Header file for the connectivity to the database
require_once('Connections/dbconfig.php');

  mysql_select_db($database_dbconfig, $dbconfig);
  // If I use the following line of code for connectivity then it works perfectly fine:
  //$dbh = new PDO('mysql:host=localhost;dbname=rare','root','');
  $dbh= $dbconfig;
  $q = 'select resident_id,u_first,u_last from z_events group by resident_id';
  /*
  The following error will occur when I try to make a connection from the header file:
  Fatal error: Call to a member function prepare() on a non-object in C:\Users\QAD\Downloads\CAR\index12 - Copy.php on line 200 
  */
  $user = $dbh->prepare($q);
  $user->execute();
?>

dbconfig.php

<?php
# FileName="Connection_php_mysql.htm"
# Type="MYSQL"
# HTTP="true"
$hostname_dbconfig = "localhost";
$database_dbconfig = "rare";
$username_dbconfig = "root";
$password_dbconfig = "";
$dbconfig = mysql_pconnect($hostname_dbconfig, $username_dbconfig, $password_dbconfig) or trigger_error(mysql_error(),E_USER_ERROR); 
?>

Answer 1

您正在将mysql_ *函数与PDO函数混合使用 - 首先使用mysql_connect连接到数据库，然后使用prepare（）查询数据库。

您应该完全转移到PDO，替换此行：

$dbconfig = mysql_pconnect($hostname_dbconfig, $username_dbconfig, $password_dbconfig) or trigger_error(mysql_error(),E_USER_ERROR);

有了这个：

$dbconfig = new PDO('mysql:dbname=' . $database_dbconfig . ';host=127.0.0.1', $username_dbconfig, $password_dbconfig);

并将其放在您的其他文件中：

<?php

//Including Header file for the conectivity to the database
require_once('Connections/dbconfig.php');

  $dbh = $dbconfig;
  $q = 'select resident_id,u_first,u_last from z_events group by resident_id';
  $user = $dbh->prepare($q);
  $user->execute();
?>

Answer 2

试一下

$connection = mysql_connect("localhost","root","") or die(mysql_error());
$db = mysql_select_db("database_name") or die(mysql_error());

Answer 3

将您的数据库选择更改为此

mysql_select_db($database_dbconfig);

PHP中的数据库连接 - 意外错误

3 个答案: