獲取SQL記錄

Question

當我運行這段代碼，它返回話題罰款...

$query = mysql_query("SELECT topic 
FROM question 
WHERE id = '$id'"); 
    if(mysql_num_rows($query) > 0) { 
     $row = mysql_fetch_array($query) or die(mysql_error()); 
     $topic = $row['topic']; 
    } 

但是當我改變這一點，它不會運行在所有。爲什麼發生這種情況？

$query = mysql_query("SELECT topic, lock 
FROM question 
WHERE id = '$id'"); 
    if(mysql_num_rows($query) > 0) { 
     $row = mysql_fetch_array($query) or die(mysql_error()); 
     $topic = $row['topic']; 
     $lockedThread = $row['lock']; 
     echo "here: " . $lockedThread; 
    } 

Answer 1

確保lock不是一個MySQL的關鍵字（保留字），你可以在字段列表BACKTICK它（`lock`）：

SELECT `topic`, `lock` 
... 

MySQL 5.6 Reserved Words