For a data warehouse fact table, which of the following block storage table parameter settings can improve full full-table scan performance on large tables?
A . Set PCTUSED to 50 percent% of PCTFREE.
B . Set PCTFREE to 50 percent% of PCTUSED.
C . Set PCTUSED low.
D . Set PCTUSED high.
E. Minimize PCTFREE.
Explanation:
Answer E: Because we're looking to perform full-table scans against traditionally large tables, we want to make sure that we read as many rows as we can for each I/O. By minimizing PCTFREE, we will probably fit more rows into a block (higher block density) and improve the performance of full-table scans. PCTUSED is irrelevant because we should not have delete activity in a data warehouse fact table.
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