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List Prefetch

List Prefetch is an Query Optimizer routine that extracts the Record IDs (RIDs) that match a specific search criteria from a particular index. These RIDs are sorted in ascending order, thereby enabling sequential table access. By accessing the table data pages in a sequential fashion, disk head seek time can be drastically reduced and data page prefetching performed. The server considers list prefetch when table data page access is required, when a multiple index access condition is detected, or if data needs to be retrieved in physical order.

Note: List prefetch can be affected by the size of the RID Pool buffer. See the section Improving Production Processing for more information.
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