The cardinality represents the estimated number of rows returned from the access plan operator.
基数(cardinality)表示访问计划操作符所返回的行的估计数目。
Estimated rows: estimated number of rows returned, as estimated by the optimizer for the statement.
Estimated Rows：优化器估计此语句返回的行数。
The optimizer calculates its cardinality estimate — that is, the estimated number of rows returned by the query — based on the statistics available.
优化器根据可用的统计信息计算基数的估计值，即预计查询返回的行数。
To the right of each table reference is the table cardinality (in terms of both number of records and number of pages) and the estimated number of qualified rows.
每个表引用的右边是表基数(依据记录的数量和页面的数量)以及合格行的估计数量。
The total number of rows, estimated by the optimizer, is 2.176.
优化器估计的总行数是 2.176。
The plan segment from the access plan in Listing 2 indicates that the IXSCAN operation will return an estimated number of 4.85057 (approximately 5) rows.
清单2中的访问计划片段表明IXSCAN操作估计将返回4.85057(约5)行。
The plan segment from the access plan in Listing 2 indicates that the IXSCAN operation will return an estimated number of 4.85057 (approximately 5) rows.
清单2中的访问计划片段表明IXSCAN操作估计将返回4.85057(约5)行。
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