Question

请先查看此代码：

$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 weekcheck 的值来自不同的页面。我想要的只是，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，已使用 $ sqlx 。请提出建议。

Answer 1

if(!empty($_POST['weekcheck'])) // check whether its not blank
    {
       $where = " where `week` =".$_POST['weekcheck'];
    }
    else
    {
       $where = ""; // blank string 
    }

    // so if weekcheck is posted then what ever the value is will pass to the sql query.
    //for e.g. $_POST['weekcheck']=1;
    //then sql statement will be SELECT week, name, date FROM lucky where `week` = 1
    //for e.g. $_POST['weekcheck']=2;
    //then sql statement will be SELECT week, name, date FROM lucky where `week` = 2
    //else if not posted weekcheck
    //then sql statement will be SELECT week, name, date FROM lucky


    $sql = "SELECT week, name, date FROM lucky ".$where;

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

你从这里得到它..！：）

Answer 2

试试这个

$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 );
$retvalxx = mysql_query( $sqlxx, $conn );

  $fetch = $_POST['weekcheck'];



    if($fetch == 1)
      {
        while($row3 = mysql_fetch_array($retval, MYSQL_ASSOC))
         {
            //do some thing
         }
      }

    if($fetch == 2)
      {
        while($row2 = mysql_fetch_array($retvalxx, MYSQL_ASSOC))
         {
            //do some thing
         }
      }

Answer 3

没有测试此代码，但它应该运行，它还会清理你的周检查整数

<?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']}";

}

?>

回复你的评论：

将$ one_and_only_sql的行替换为：

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

如何使用PHP从数据库中获取特定值

3 个答案: