Shared Server Changes

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SQL statement being executed can take advantage of the fact that the data stored in the sorted hash cluster is in the order of CUSTOMER_ID and CALL_DATE and will sort, or not sort, as required. For example, this query will not require a sort operation:

 Select booth_number, customer_id, emp_id, call_duration from call_center_detail order by customer_id; 

But the following query will require a sort operation:

 Select booth_number, customer_id, emp_id, call_duration from call_center_detail order by emp_id; 

NOTE
Statistics are, of course, critical to the successful use of a sorted hash cluster.

Shared Server Changes

Oracle Database 10g includes some changes to Oracle shared server architecture. These include

Changes to shared server configuration

MTS parameters become obsolete

Addition of a new V$DISPATCHER_CONFIG view

Capability to trace shared server sessions

Let's look at each of these features in more detail next.

Changes to Shared Server Configuration

In prior versions of Oracle Database, you had to configure at least one dispatcher in order to use Oracle's shared server features. Now, Oracle 10g is shared server ''aware" by default and all you need to do is set the shared_servers parameter to a value greater than 0 to enable this feature. While other shared server parameters are still available to be used (and ultimately tune the shared server architecture), none needs to be set in order to use the shared server architecture.

As with Oracle9i, the shared_servers parameter is dynamic in nature, so you can choose to enable or disable the feature at will via the alter system command. Since the database requires no other parameters to be set to use shared server features, you can easily enable this architecture without recycling the database, should you determine that your database will benefit from it.