Q:

How do I use group by in DynamoDB?

I'm using PHP with DynamoDB. I'm fetching some records by using 'scan'. I wanted to use Group By with this query just like in MySQL. Please help.
 $result = $client->scan([
            'ExpressionAttributeValues' => [
                ':v1' => [
                    'S' => '2002',
                ]
            ],
            'FilterExpression' => 'userId = :v1',
            'TableName' => $this->table,
        ]);
        return $result;

A:

There is no GROUP BY in Dynamo DB. It is a NoSQL database, so it is not like SQL. 
You can, however, use HiveQL to query Dynamo in a SQL-like fashion.

