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| Overview: The SPD Engine |
Features That Enhance I/O Performance
| Overview of I/O Performance Enhancements |
The SPD Engine has several new features that enhance I/O performance. These features can dramatically increase the performance of I/O bound applications, in which large amounts of data must be delivered to the application for processing.
| Multiple Directory Paths |
You can specify multiple directory paths and devices for each component type because the SPD Engine can reference multiple physical files across volumes as a single logical file. For very large data sets, this feature circumvents any file size limits that the operating system might impose.
| Physical Separation of the Data File and the Associated Indexes |
Because each component file type can be stored in a different location, file dependencies are not a concern when deciding where to store the component files. Only cost, performance, and availability of disk space need to be considered.
| WHERE Optimization |
The SPD Engine automatically determines the optimal process to use to evaluate observations for qualifying criteria specified in a WHERE statement. WHERE statement efficiency depends on such factors as whether the variables in the expression are indexed. A WHERE evaluation planner is included in the SPD Engine which can choose the best method to use to evaluate WHERE expressions that use indexes to optimize evaluation.
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