Execution characteristics

Following is a series of events that could take place in an Adaptive Server environment with the configuration described in this example:

  1. A client logs in to Adaptive Server as “L1” using OLTP.

    • Adaptive Server determines that OLTP is EC1.

    • “L1”does not have an execution class. However, because “L1” logs in to the OLTP application, Adaptive Server assigns the execution class EC1.

    • “L1” executes the stored procedure at a high priority since the object has been assigned execution class EC1.

  2. A client logs in to Adaptive Server as “L1” using isql.

    • Because isql is EC3, and “L1” is not bound to an execution class, “L1”executes with EC3 characteristics. This means it runs at low priority and has affinity with the highest numbered engine (as long as there are multiple engines).

    • When “L1”executes sp_xyz, its priority is raised to high because the stored procedure is EC1.

  3. A client logs in to Adaptive Server as “sa” using isql.

    • Adaptive Server determines the execution classes for both isql and “sa”, using the precedence rule. Adaptive Server runs the system administrator’s instance of isql with EC1 attributes. When the system administrator executes sp_xyz, the priority does not change.

  4. A client logs in to Adaptive Server as “L2” using isql.

    • Because both the application and login are EC3, there is no conflict. “L2” executes sp_xyz at high priority.