| 摘要 |
Methods, systems and articles of manufacture for selectively maintaining query implementation information. A user is able to set a Predictive Query Threshold which will be honored by a database system to determine for which queries information will be collected. In one embodiment, the decision about whether to collect information for a query is made before the query starts to run (i.e., before the plan is executed) by comparing the Predictive Query Threshold to some cost factor (e.g. estimated runtime). In another embodiment, each query may be monitored but the query implementation information is only selectively logged. Specifically, the determination as to whether query implementation information for a query should be logged is made after the query implementation information is collected.
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