在为Microsoft SQL Server创建统计信息时，列顺序是否重要？ [英] Does column order matter when creating statistics for Microsoft SQL Server?

问题描述

数据库引擎优化顾问建议为我们的几个查询创建一些统计信息。结果是，其中一些是相同的只是列顺序在CREATE STATISTICS命令中不同。例如：

  CREATE STATISTICS [StatName1] ON [dbo]。[table1]（[column2]，[column1]）
 
 CREATE STATISTICS [StatName2] ON [dbo]。[table1]（[column1]，[column2]）
  

是相同的还是以不同的方式处理？

沿着相同的行，我可以结合给定表的CREATE STATISTICS命令吗？如果顾问在同一列上为3个不同的查询推荐了3个不同的统计数据，我可以对所有3个列执行一个单独的创建命令，例如

  CREATE STATISTICS [StatName1] ON [dbo]。[table1]（[column1]，[column3]）
 
 CREATE STATISTICS [ column2]）
  

到

  CREATE STATISTICS [StatName1] ON [dbo]。[table1]（[column1]，[column2]，[column3]）
   
 
 
感谢
解决方案
同一列上的多个统计数据是无用的。只需要一个。 
订单无关紧要。
 
The Database Engine Tuning Advisor has recommended the creation of some statistics for several of our queries.  Turns out that some of these are the same just the column order is different in the CREATE STATISTICS command.  For example:
CREATE STATISTICS [StatName1] ON [dbo].[table1]([column2], [column1])

CREATE STATISTICS [StatName2] ON [dbo].[table1]([column1], [column2])
are these the same or are they treated differently?

Along the same lines can I combine CREATE STATISTICS command for a given table? If the Advisor recommended 3 different stats on the same column for 3 different queries can I do a single create command for all 3 columns e.g.
CREATE STATISTICS [StatName1] ON [dbo].[table1]([column1], [column3])

CREATE STATISTICS [StatName2] ON [dbo].[table1]([column1], [column2])
into 
CREATE STATISTICS [StatName1] ON [dbo].[table1]([column1], [column2], [column3])
Thanks
解决方案
multiple stats on the same column are useless. Only one is needed.
order is irrelevant.

                        
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