BadMethodCall exception

when my code runs these lines:


try {
   $result = $sdk->query([array(
       'TableName' => $tableName,
       'KeyConditionExpression' => 'campaign = _campaign and compare_date = : d_compare_date',
       'ExpressionAttributeValues' => array(
           '_campaign' => array('S' => $campaign),
           ':d_compare_date' => array('N' => $d)
       ),
   )]);

I am getting this error:

An uncaught Exception was encountered
Type: BadMethodCallException
Message: Unknown method: query.
Filename: C:\xampp\htdocs\sub_crud\vendor\aws\aws-sdk-php\src\Sdk.php
Line Number: 330
Backtrace:
File: C:\xampp\htdocs\sub_crud\application\controllers\Configure.php
Line: 1172
Function: __call
File: C:\xampp\htdocs\sub_crud\application\controllers\Configure.php
Line: 1172
Function: query
File: C:\xampp\htdocs\sub_crud\index.php
Line: 316
Function: require_once

At the top of my controller i have these lines:

use GuzzleHttp\Stream\Stream;   //for the s3 interface
use Aws\DynamoDb\Exception\DynamoDbException;
use Aws\DynamoDb\Marshaler;

How would I go about solving this? The faces are not in the actual code. It is ':ess_'

proof that an old dog can learn new tricks