Getting data from SimpleDB using PHP

Question

How do I get data out of SimpleDB? All I wanted to do was put data in and then get data out. It looks like the data is not easy to get out and in the end will require computing power to extract by looping etc. Am I correct?

Here is my code to extract the data:

<?php
// Include the SDK
require_once 'sdk.class.php';

// Instantiate
$sdb = new AmazonSDB();

$select_expression = 'SELECT * FROM ' . $domain_name;
$next_token = null;

do {
  if ($next_token) {
    $response = $sdb->select($select_expression, array(
        'NextToken' => $next_token,
      ));
  } else {
    $response = $sdb->select($select_expression);
  }

  // Get Data for row 
  $body = $response->body->to_array()->getArrayCopy();

  echo "ID: " . $msgId . "<br>";

  $next_token = isset($response->body->SelectResult->NextToken)
    ? (string) $response->body->SelectResult->NextToken
    : null;
}
while ($next_token);

echo "<br>";
?>

Here is the extract of the data I'm trying to extract.

All I want to get is the following variables:

msgId (the Name), msgType, msgAddress, msgText, msgSubmitDate

If I can get it using $msgType = Body->SelectResult->Item->Name or something like that.

I think I need another loop inside the Token loop, to loop through the data. Any help? — andrebruton, Sep 02 '12 at 16:00

score 3 · Answer 1 · answered Oct 05 '12 at 07:55

3

Using XPath is going to perform about 100x faster. I haven't tested this code, but the XPath expression should be pretty close:

$msgAddress = (string) $response->body->query('//Attribute[Name[text()="msgAddress"]]/Value')->first();

answered Oct 05 '12 at 07:55

Ryan Parman

6,855
1
29
43

score 2 · Answer 2 · answered Sep 02 '12 at 16:44

I figured it out using some old Tarzan code. This works for a 2 dimensional array (data similar to a standard database)

Here is the working code:

<?php
// Include the SDK
require_once 'sdk.class.php';

// Instantiate
$sdb = new AmazonSDB();

$select_expression = 'SELECT * FROM ' . $domain_name;
$next_token = null;

do {
  if ($next_token) {
    $response = $sdb->select($select_expression, array(
        'NextToken' => $next_token,
    ));
  } else {
    $response = $sdb->select($select_expression);
  }

  // Get Data for row 
  foreach ($response->body->SelectResult->Item as $item) 
    {
        $msgId = $item->Name;
      foreach ($item->Attribute as $attr)
        {
              if ($attr->Name == 'msgAddress') {
                  $msgAddress = $attr->Value;
                }
              if ($attr->Name == 'msgType') {
                  $msgType = $attr->Value;
                }
              if ($attr->Name == 'msgSubmitDate') {
                  $msgSubmitDate = $attr->Value;
                }
              if ($attr->Name == 'msgText') {
                  $msgText = $attr->Value;
                }
        }

      echo "<br>msgId: $msgId<br>";
      echo "msgAddress: $msgAddress<br>";
      echo "msgType: $msgType<br>";
      echo "msgSubmitDate: $msgSubmitDate<br>";
      echo "msgText: $msgText<br><br>";

    }

  $next_token = isset($response->body->SelectResult->NextToken)
    ? (string) $response->body->SelectResult->NextToken
    : null;
}
while ($next_token);

echo "<br>";
?>

Working code available on our Github https://github.com/andrebruton/SimpleDB-PHP-Example — andrebruton, Sep 02 '12 at 17:57

score 1 · Answer 3 · answered Sep 02 '12 at 15:32

1

$body = $response->body->to_array()->getArrayCopy();
echo "ID: " . $msgId . "<br>";
//but $msgId is not set

answered Sep 02 '12 at 15:32

Solo Omsarashvili

940
2
11
16

Getting data from SimpleDB using PHP

3 Answers3