无法使用PHP从SQLite检索数据

Question

这是我第一次尝试使用SQLite，我试图从SQLite中检索数据，但我没有成功，也没有抛出任何异常。

我相应的代码如下：

$sql_query = "SELECT * FROM `item` WHERE combo LIKE '" . $value . "' LIMIT 1;"; 
     try { 
      /*** connect to SQLite database ***/ 
      $dbh = new PDO("sqlite:src/mydb.s3db"); 
      foreach ($dbh->query($sql_query) as $row) { 
       $name = $row['name']; 
       echo "name".$name; 
       $style = $row['style']; 
       echo $style; 
       $appr = $row['appr']; 
       echo $appr; 
       $style = $row['style']; 
       echo $style; 
      } 

     } catch(PDOException $e) { 
      //echo $e -> getMessage(); 
      echo "problem with DB"; 
      echo "<br>"; 
     } 

请指导我这个。 谢谢。

---

//phpnifo();

PDO

PDO support enabled | PDO drivers mysql, sqlite, sqlite2

PDO_SQLITE

PDO Driver for SQLite 3.x enabled | PECL Module version (bundled) 1.0.1 $Id: pdo_sqlite.c 293036 2010-01-03 09:23:27Z sebastian $ SQLite库3.3.7

Answer 1

一）告诉PDO您希望使用的例外而不是把有效载荷paraemters到SQL语句中使用报告错误

$dbh = new PDO("sqlite::memory:"); 
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); 

二）准备参数化的语句

try { 
    $stmt = $dbh->prepare('SELECT * FROM `item` WHERE combo LIKE ? LIMIT 1'); 
    $stmt->execute(array($value)); 
    foreach($stmt as $row) { ... 

C）如果你仍然没有得到任何输出，尝试无条件打印某些东西的代码。例如。一个SELECT Count（*）将总是返回至少一条记录（如果没有发生错误）。

$stmt = $dbh->prepare('SELECT Count(*) as cnt FROM `item` WHERE combo LIKE ?'); 
$stmt->execute(array($value)); 
foreach($stmt as $row) { 
    echo 'Count: ', $row['cnt'], "\n"; 
} 
$stmt = null; 

---

编辑：自包含的示例

<?php 
ini_set('display_errors', true); 
error_reporting(E_ALL); 

echo "start\n"; 

try { 
    $dbh = new PDO("sqlite::memory:"); 
    $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); 
    $dbh->setAttribute(PDO::ATTR_EMULATE_PREPARES, false); 
    setup($dbh); 


    $stmt = $dbh->prepare('SELECT * FROM item WHERE combo LIKE ? LIMIT 1'); 
    $stmt->execute(array('comboB')); 
    foreach($stmt as $row) { 
     echo 
      $row['name'], " ", 
      $row['style'], " ", 
      $row['appr'], "\n" 
     ; 
    } 
} 
catch(Exception $ex) { 
    var_dump($ex); 
} 
echo "done.\n"; 

function setup($dbh) { 
    $dbh->exec(' 
     CREATE TABLE item (
      combo TEXT, 
      name TEXT, 
      style TEXT, 
      appr TEXT 
     ) 
    '); 
    $stmt = $dbh->prepare('INSERT INTO item (combo,name,style,appr) VALUES (?,?,?,?)'); 
    $stmt->execute(array('comboA','nameA','styleA','apprA')); 
    $stmt->execute(array('comboB','nameB','styleB','apprB')); 
    $stmt->execute(array('comboC','nameC','styleC','apprC')); 
}