如何降低下述查询的聚簇索引扫描成本
DECLARE @PARAMVAL varchar(3)
set @PARAMVAL = 'CTD'
select * from MASTER_RECORD_TYPE where RECORD_TYPE_CODE=@PARAMVAL
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如果我运行上面的查询它显示索引扫描99%
请在下面找到我的表格特点:

我在下面粘贴了表格的索引:
CREATE TABLE [dbo].[MASTER_RECORD_TYPE] ADD CONSTRAINT [PK_MASTER_REPORD_TYPE] PRIMARY KEY CLUSTERED
(
[Record_Type_Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 80) ON [PRIMARY]
GO
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请建议我如何降低索引扫描成本?
在下面的代码中,我正在使用当前日期和时间,并在此日期和时间的帮助下生成文件名。我的问题是,它给我的输出没有前导零:
Dim strDateTime As String = DateTime.Now.Day.ToString() & "" & _
DateTime.Now.Month.ToString() & "" & DateTime.Now.Year.ToString() & "" & _
DateTime.Now.Hour.ToString() & "" & DateTime.Now.Minute.ToString() & "" & _
DateTime.Now.Second.ToString() & DateTime.Now.Millisecond.ToString()
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例如,我的查询当前给出如下输出:
假设时间是 1:5:30 :: hh:mm:ss
所需的输出是: 01:05:30
我该如何实现?