Google BigQuery : transpose rows in columns
<p>I know there are some threads opened already, but below is my request.
I want to put all items purchased by a customer from rows to column, key being the order_id.
Below is a sample of the data as I have approx. 1M rows.</p>

<p><strong>1) I want this :</strong></p>

<pre><code>Row            |order_id         |sku    
1              |600007637        |M0532OCAL_M900_TU  
2              |600007637        |S9035OECD_M930_TU  
3              |600007613        |3SN002VMM_H000     
4              |600007613        |3SN171XGU_H860
</code></pre>

<p><strong>2) To become this</strong> </p>

<pre><code>Row       |order_id          |sku                     |sku2                 
1         |600007637         |M0532OCAL_M900_TU       |S9035OECD_M930_TU    
2         |600007613         |3SN002VMM_H000          |3SN171XGU_H860
</code></pre>

<p>Can someone help ?</p>