Question

我遇到的问题是只能从mysqli一次打开一个结果集。特别是我尝试循环选择查询并在执行操作后更新该查询中的列。

$db = new mysqli($DBServer, $DBUser, $DBPass , $DBName);
$sql = 'SELECT UPRN, POSTCODE FROM T_TEMP';
$stmt = $db->prepare($sql);
$stmt -> Execute();

<Create an array from the above select statement as i understand that mysqli can 
only hold one result set at once (seems odd). I am unsure how to do this such that
i can then reference UPRN and POSTCODE later>

$stmt->Close();

$sql = 'update T_TEMP set LAT = ?, LONG = ? where UPRN = ?';
$stmt = $db ->prepare($sql);  

<loop through that array built above grabbing UPRN and POSTCODE as you go through>

$postcode = urlencode(<Reference the postcode in the array>);
$request_url = "http://maps.googleapis.com/maps/api/geocode/xml?address=".$postcode."&sensor=false"; 
$xml = simplexml_load_file($request_url);

$lat = round(floatval($xml->result->geometry->location->lat),4);
$long = round(floatval($xml->result->geometry->location->lng),4);

$stmt -> bind_param('ddi',$lat,$long,$UPRN);

$stmt -> Execute();

<end loop>

我正在努力将第一个查询的结果导入数组，然后在循环中引用该数组，以便我可以设置值。任何帮助非常感谢！

Answer 1

不要使用mysqli。请改用PDO。在后一种情况下，这个所需的代码将是一行：

include 'db.php';
$sql  = 'SELECT UPRN, POSTCODE FROM T_TEMP';
$stmt = $db->prepare($sql);
$stmt->execute();
$array = $stmt->fetchAll(); // here you are

Answer 2

在向正确方向转向后，我结束了将结果集读入数组，然后循环遍历该数组。（此评论已经被投票，但我正在编辑它以便其他人更容易找到。）

您不能打开两个mysqli查询，因为服务器只允许您在内存中保留一个（实际上在服务器上）。所以你将第一个查询读入php数组，然后循环执行该数组中的mysqli语句。

$vInteger =1; //This is just an example variable

$sql ='select column from table where column = ?'; //select with a passed value

$stmt = db->prepare($sql);

$stmt-> bind_param('i', $vInteger); //again, this could be a string, double or integer

$stmt->execute();

$result = $stmt->get_result(); //retrieves the results from the server into a class

while ($row = $result->fetch_assoc(){
   $Array[] = $row; //reads the rows into a new array
} 

$stmt -> free_result(); //Drop the mysqli bit cause you are going to need it again! :)

foreach($Array as $item){
  $item['Column']; // this is the column name from your original query


 // Of course in here you might want to do another mysqli query with the prepare etc etc and reference the $item.

 }

如果你决定使用对我有用的mysqli，我认为get_result会创建一个mysqli结果类，你可以应用fetch_assoc方法..

mysqli来自更新查询中使用的选择查询

2 个答案: