title: DynamoDB : Query always returning null
body: <p>I am quite new on DynamoDB, I just create a table where I inserted some dummy rows just to test the read / write functions. </p>
  
  <p><a href="https://i.stack.imgur.com/V5HPD.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/V5HPD.png" alt="enter image description here"></a></p>
  
  <p>Here is my data. </p>
  
  <p>I create a Lambda to access these data, via Partition Key ok Sort Key but I ended up with a null return every time :'( </p>
  
  <p>Here is the code of my lambda : </p>
  
  <pre><code>    const dynamodb = new AWS.DynamoDB.DocumentClient({apiVersion: '2012-08-10', region: 'eu-west-1'});
  
  exports.handler = async (event,context,callback) =&gt; {
      var params = {
          TableName : "DontMissAPlaceTable",
          KeyConditionExpression: "Partition_Key = :id",
          ExpressionAttributeValues: {
              ":id": {"S" :  "media_001"}
          }
      };
      dynamodb.query(params, function(err, data) {
          if (err) {
              console.log(err, err.stack);
              callback(null, {
                  statusCode: '500',
                  body: err
              });
          } else {
              console.log(data)
              callback(null, {
                  statusCode: '200',
                  body: data
              });
          }
      })
  
  };
  </code></pre>
  
  <p>I first thought it was lack of access to the table but it seems I have the right permissions. </p>
  
  <p><a href="https://i.stack.imgur.com/D5tdT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/D5tdT.png" alt="enter image description here"></a></p>
  
  <p>I am quite sure it's a dummy problem but i can't figure it out ... </p>
  
  <p>Thanks for help :D</p>