Teradata WA sets the evaluation order of workloads in the Candidate Workloads tree after every workload split or merge. The execution of queries can be determined for workloads for classification overlapping.
The following table describes how evaluation order is determined for workloads in the Candidate Workload tree.
Example | Description | Evaluation Order |
---|---|---|
1 | A workload such as WD-TWA (a parent workload - Account=TWA and evaluation order of 5) is analyzed with the correlation parameter UserID (TDWM). WD-TWA is split into a new workload (WD-TDWM). |
WD-TWA is set at a higher evaluation order because of the parent workload (WD-TWA) WD-TDWM-classification (Account=TWA and UserID=TDWM). The evaluation order is five. WD-TWA-classification (Account=TWA). The evaluation order is six. |
2 | WD-TDWM is split into a new workload with Estimated Processing Time as its distribution parameter. | WD-TDWM-Estimated Processing Time-classification (Account=TWA and UserID=TDWM and Estimated Processing Time>10 seconds). The evaluation order is five. WD-TDWM-classification (Account=TWA and UserID=TDWM). The evaluation order is six. WD-TWA-classification (Account=TWA). The evaluation order is seven. |
3 | The workload in Example1 is split using Copy and Move. | Evaluation order results are the same as Example 1. |
4 | The workload in Example 1 with a wild card. | The parent workload of a wild card workload will always have a higher evaluation order. |
5 | For workload merging, Teradata WA sets the same target workload evaluation order (the workloads to be merged) as the merged workload. | WD-A (Account=A). Evaluation order is ten. WD-B (Account=B). Evaluation order is 11. WD-A-Estimated Processing Time (Account=A and Estimated Processing Time>10 seconds). The evaluation order is 12. WD-A and WD-B are merged with WD-A-Estimated Processing Time (target workload). WD-Merge1 (Account in (A,B) and Estimated Processing Time>10 seconds). The evaluation order is 12. |