Database Reference
In-Depth Information
Figure 2-12.
Mirror pattern
Combining Patterns
The previous design patterns provide the necessary basis to build systems with SQL Azure. Some of
these patterns can be used as is, but you're very likely to combine patterns to deliver improved solutions.
This section describes some useful combinations.
Transparent Branching + RWS
Figure 2-13 shows the transparent branching and the read-write shard patterns combined. This pattern
can be used to offload into the cloud storage of historical data that an existing Enterprise Resource
Planning (ERP) application generates. In this example, the shard provides a way to ensure high
throughput by using asynchronous round-robin calls into SQL Azure databases.
This pattern offers the following advantages:
•
Transparent data transfer. In this case, the transparent branching pattern
copies an existing application's data into cloud databases without changing
a single line of code in the existing application.
•
High performance.
To ensure high performance and throughput, the round-
robin shard pattern is used along with asynchronous calls into the cloud.
•
Scalable.
When using a shard, it's very simple to expand it by adding a new
SQL Azure database into the cloud. If implemented correctly, the shard
automatically detects the new database and storage capacity, and
throughput automatically increases.
