SQL: SQL Server ROW_NUMBER Using PARTITION to Group Row Numbers

I recently ran into a problem where I needed to return data representing financial charges against a recurring subscription. I needed to have 1 query that returned the subscription data with its first charge and a second query that returned the subscription data with all subsequent charges. I accomplished this use the ROW_NUMBER function using a PARTITION. The PARTITION feature essentially lets you use the ROW_NUMBER function over parts of the data. In this case, the ROW_NUMBER function using a parent SubscriptionId as the value to iterate over and each unique SubscriptionId had its own iterator.

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SELECT			
			Subscription.Id AS 'Subscription Id'
			,SubscriptionCharges.Id AS 'Charge On Subscription Id'
			,SubscriptionCharges.ChargeDate AS 'Charge On Subscription Date'
			
			,ROW_NUMBER() OVER(PARTITION BY SubscriptionCharges.SubscriptionId ORDER BY SubscriptionCharges.Id ASC) AS ChargeCount

FROM		Subscriptions
			JOIN SubscriptionCharges ON Subscription.Id = SubscriptionCharges.SubscriptionId

ORDER BY	Subscription.id