MySQL多个条件

Question

我想搜索我的数据库，我最初只用一个条件工作，但现在有四个，它只会刷新页面，删除字段输入。

我试过只使用逗号，但这似乎也不起作用。我一直无法在Google上找到有关他们是极限的任何信息，但也没有使用四种条件的示例。有没有正确或更好的方法可以尝试？

if(isset($_POST['search'])){ 
    $lname = trim($_POST['lname']); 
    $address = trim($_POST['address']); 
    $street = trim($_POST['street']); 
    $city = trim($_POST['city']); 
    $county = trim($_POST['county']); 

    if($lname==""){ 
     $error[] = "Provide Last Name."; 
    }elseif($address=""){ 
     $error[] = "Provide House Number/Name."; 
    }elseif($street==""){ 
     $error[] = "Provide Street."; 
    }elseif($city==""){ 
     $error[] = "Provide City."; 
    }elseif($county==""){ 
     $error[] = "Provide County."; 
    }else{ 
     try{ 
      $stmt = $conn->prepare("SELECT * FROM clients WHERE lname=lname AND address=address AND street=street AND city=city AND county=county"); 
      $stmt->execute(array("lname"=>$lname, "address"=>$address, "street"=>$street, "city"=>$city, "county"=>$county)); 
      $userRow=$stmt->fetch(PDO::FETCH_ASSOC); 

      if($userRow==''){ 
       $user->redirect('./results.php?new='.$lname.$street); 
      }else{ 
       if($userRow['rating'] == 'good'){ 
        $user->redirect('./results.php?good='.$lname.$street); 
       } 
       if($userRow['rating'] == 'cautionextra'){ 
        $user->redirect('./results.php?cautionextra='.$lname.$street); 
       } 
       if($userRow['rating'] == 'cautiondiscount'){ 
        $user->redirect('./results.php?cautiondiscount='.$lname.$street); 
       } 
       if($userRow['rating'] == 'cautionlate'){ 
        $user->redirect('./results.php?cautionlate='.$lname.$street); 
       } 
       if($userRow['rating'] == 'badnopay'){ 
        $user->redirect('./results.php?badnopay='.$lname.$street); 
       } 
       if($userRow['rating'] == 'badabusive'){ 
        $user->redirect('./results.php?badabusive='.$lname.$street); 
       } 
      } 
     } 
     catch(PDOException $e){ 
      echo $e->getMessage(); 
     } 
    } 
} 

在phpMyAdmin执行SELECT * FROM clients WHERE lname=lname AND address=address AND street=street AND city=city AND county=county返回所有行的，伟大的，但我var_dump($userRow);，它显示的其中一个我试图寻找不同行的结果。

Answer 1

的问题是，使用为search列的equality test使得它很难得到与之匹配的任何行，因为：

• 输入的值必须匹配与表格行中的列完全相同。
• 必须输入所有搜索栏。如果它们是空的，那么它们将永远不匹配任何行。

该方法与搜索领域是：

• 尝试approximately match的input value与column value使用like代替=作为比较操作。
• 作出empty input value匹配任何列值。即忽略测试

所供给的代码将生成的代码：column like %为空的输入或将包装在通配符的输入值：column like %input value%

Untested source at Pastebin.com

未经测试的代码：

<?php // completely untested code... 
    $stmt = $conn->prepare("SELECT * 
          FROM clients 
          WHERE lname like :lname 
          AND address like :address 
          AND street like :street 
          AND city like :city 
          AND county like :county"); 

    $stmt->execute(array("lname" => empty($lname) ? '%' : '%'. $lname .'%', 
         "address" => empty($address) ? '%' : '%'. $address .'%', 
         "street" => empty($street) ? '%' : '%'. $street .'%', 
         "city" => empty($city) ? '%' : '%'. $city .'%', 
         "county" => empty($county) ? '%' : '%'. $county .'%')); 

    $userRow = $stmt->fetch(PDO::FETCH_ASSOC); 

Answer 2

你不需要：":lname"在execute(array(...))只是使用前面没有冒号的索引："lname"。

全线：

$stmt->execute(array("lname"=>$lname, "address"=>$address, "street"=>$street, "city"=>$city, "county"=>$county));