如果语句涉及到更大的表格和两个或者更多个表的连接的话,查询访问计划就很可能会因为基数估计值的提高而改变。
Statements involving larger tables and joins of two or more tables are more likely to exhibit a change in query access plan as a result of the improved cardinality estimate.
换句话说,优化器过高估计了本地谓词对表格的选择性。
In other words, the optimizer overestimated the selectivity of the local predicates on the table.
联邦决策者们估计美国的“自然”失业率——换句话说就是同稳定的通胀率相平衡的最低失业率应该维持在6%甚至更低(见右侧表格)。
Fed policymakers reckon America's "natural" unemployment rate-that is, the lowest compatible with stable inflation-is at or below 6% (see right-hand chart).
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