php - 如何使用 PHP 从数据库中获取特定值

Question

请先看一下这段代码:

$dbhost = xxxx;
$dbuser = xxxxxxx;
$dbpass = xxxxxxxxx;
$conn = mysql_connect($dbhost, $dbuser, $dbpass);

$sql = SELECT week, name, date FROM lucky;
$sqlx = SELECT week, name, date FROM lucky WHERE week = 1;
$sqlxx = SELECT week, name, date FROM lucky WHERE week = 2;
$retval = mysql_query( $sqlx, $conn );

while($row = mysql_fetch_array($retval, MYSQL_ASSOC))
{
  $fetch = $_POST['weekcheck'];
  if($fetch == 1)
  {
    echo "{$row['week']}";
  }
}

此代码中的weekcheck 值来自不同的页面。我想要的是，如果 $fetch == 1，那么我想运行 $sqlx，如果 $fetch == 2，那么我想要运行$sqlxx。但在$retval中，已经使用了$sqlx。请提出一些建议。

Answer 1

尚未测试此代码，但它应该运行，它还会清理您的 weekcheck 整数

<?php
$dbhost = xxxx;
$dbuser = xxxxxxx;
$dbpass = xxxxxxxxx;
$conn = mysql_connect($dbhost, $dbuser, $dbpass);

$one_and_only_sql = "SELECT week, name, date FROM lucky".(intval($_POST['weekcheck'])>0)?" WHERE week =".(intval($_POST['weekcheck'])):"";

$retval = mysql_query( $one_and_only_sql, $conn );

while($row = mysql_fetch_array($retval, MYSQL_ASSOC))
{

    echo "{$row['week']}";

}

?>

回复您的评论:

将 $one_and_only_sql 行替换为:

$one_and_only_sql = "SELECT week, name, date FROM lucky".(intval($_POST['weekcheck'])>0)?" WHERE week = 'Week ".str_pad(strval(intval($_POST['weekcheck'])), 2, "0", STR_PAD_LEFT)." 2014'":"";