php - 检查并更新数据库条目 php

Question

如何在 php 中检查数据库条目的值以及当其 0 时将其更新为 1？

目前，即使我自己在数据库中将 0 设置为 1，它总是会返回 Number Notused...

表:

================================================== =========

MasterNumbers:
number          |   used
01513242        |   0
01012233        |   0
23566545        |   0

================================================== =========

代码:

$name = "01513242";
$checkForUsed  = mysql_query("SELECT * FROM MasterNumbers WHERE `used`= '$name'");
$numrowsUsed = mysql_num_rows($checkForUsed);

if ($numrowsUsed == 0 )
{
    //update used (on 01513242) form 0 to 1
    die("Number Not used");
}
else
{
    die("Number is used");
}

Answer 1

我没有检查以下类，因为我不想为此设置数据库。像这样的类应该可以完成这项工作。

<?php
    class update_numrow_class{
        // Database settings
        protected $_mysqli = false;
        protected function __construct($number){
            $this->username => 'db_username',
            $this->password => 'db_password',
            $this->host => 'localhost',
            $this->database => 'db_name',
            $this->charset => 'utf8',
            $this->number => $number
        }

        // Function to connect to the database
        function connect(){
            $mysqli = new mysqli($this->host, $this->username, $this->password, $this->database);
            if ( $mysqli->connect_errno ) {
                $this->_mysqli = false;
            }else {
                $mysqli->set_charset($this->charset);
                $this->_mysqli = $mysqli;
            }
        }

        // Function to execute an sql query
        function execute_query($sql){
            if($results = $this->_mysqli->query($sql)){
                return $results;
            }else{
                return false;
            }
        }

        // Function to check if the number was used
        function check_number(){
            $this->connect();
            $number_result = $this->execute_query("SELECT used FROM MasterNumbers WHERE number =" . $this->number);
            if($number_result == 0){
                return false;
            }else{
                return true;
            }
        }

        // Function to update the used value
        function update_number(){
            $number_check = $this->check_number();
            if(!$number_check){
                $this->connect();
                $update_result = $this->execute_query("UPDATE MasterNumbers SET used = 1 WHERE number = " . $this->number);
                return 'Number: ' . $this->number . ' successful updated.';
            }else{
                return 'Number: ' . $this->number . ' was already used.';
            }
        }
    }
?>

使用方式如下:

<?php
    require_once('update_numrow_class.php');
    $update_object = new update_numrow_class(01513242);
    $update_response = $update_object->update_number();
?>