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我有下一个分区视图：vwSalesOutH。它由不同数据库中名为“SalesOutH”的多个表组成。

当我使用下一个查询时，它工作正常，搜索是通过一个表 vwSalesOutH：

select vwSalesOutH.* 
from vwSalesOutH
inner  join DatesImport on vwSalesOutH.DBTypeId=DatesImport.DBTypeId and
                          vwSalesOutH.CustId=DatesImport.CustId
where vwSalesOutH.DBTypeId=2 and
vwSalesOutH.Date>='2017-01-01 00:00:00' and
vwSalesOutH.Date<='2017-01-25 00:00:00';

统计 IO：

   (6179 row(s) affected)
Table 'Workfile'. Scan count 0, logical reads 0, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'Worktable'. Scan count 0, logical reads 0, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'SalesOutH'. Scan count 1, logical reads 452, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'DatesImport'. Scan count 1, logical reads 2, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

当我使用下一个查询时，在“where”块中使用相同的日期时，我遇到了问题 - 搜索是按分区视图中的所有表进行的：

select vwSalesOutH.* 
from vwSalesOutH
inner  join DatesImport on vwSalesOutH.DBTypeId=DatesImport.DBTypeId and
                          vwSalesOutH.CustId=DatesImport.CustId
where vwSalesOutH.DBTypeId=2 and
vwSalesOutH.Date>=DatesImport.Fact_Start and
vwSalesOutH.Date<=DatesImport.Fact_End;

统计 IO：

(6179 row(s) affected)
Table 'DatesImport'. Scan count 1, logical reads 2, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'Workfile'. Scan count 0, logical reads 0, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'Worktable'. Scan count 0, logical reads 0, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'SalesOutH'. Scan count 5, logical reads 452, physical reads 0, read-ahead reads 43, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'SalesOutH'. Scan count 5, logical reads 584, physical reads 0, read-ahead reads 1, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'SalesOutH'. Scan count 5, logical reads 55717, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'SalesOutH'. Scan count 5, logical reads 12752, physical reads 0, read-ahead reads 3, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'SalesOutH'. Scan count 5, logical reads 11834, physical reads 0, read-ahead reads 8, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'SalesOutH'. Scan count 5, logical reads 11097, physical reads 0, read-ahead reads 10, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'SalesOutH'. Scan count 5, logical reads 51, physical reads 0, read-ahead reads 13, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.
Table 'Worktable'. Scan count 0, logical reads 0, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

你能给我建议来解决第二个查询吗？

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1 回答 1

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我遇到了同样的问题，问题似乎是除非分区值作为常量（未连接，非变量）提供，否则优化器无法识别要使用的分区，而是扫描所有表

即使使用选项（重新编译），对连接列的过滤也不会进行单表查找。

使用带有 Option 的变量（重新编译）进入单表查找。

于 2017-04-25T14:36:54.903 回答