The key selection process might be the trickiest part when it comes to tables. Three things to keep in mind when picking the key:
Scalability: How to be able to distribute data evenly among partitions
Efficient queries: How to avoid frequent large scans
Entity Group Transactions: How to reduce round trips to the server
Your choice of PartitionKey should achieve balance between the above, ensuring scalability, efficient querying and data consistency. Normally, you will find the most suitable property in your entity for distributing your entities into adequate partitions.
Here are some guidelines that will help you select your key:
If your entity has one key property, use this property as the PartitionKey.
If your entity has two key properties, use one as PartitionKey and the other as RowKey.
In many cases you may have more than one dominant query for your entities. You can then insert the same entity multiple times in the table with different RowKeys; this can be...