求助关于sql语句中多where条件的写法?
有一查询功能根据提供的时间段返回某字段值。 例如:
select 字段1 from 表1 where time between 时间1 and 时间2;
由于时间段会有多个 ,所以如上语句会有多条,只是时间段不同,例如:
select 字段1 from 表1 where time between 时间1 and 时间2;
select 字段1 from 表1 where time between 时间3 and 时间4;
select 字段1 from 表1 where time between 时间5 and 时间6;
……
有么有什么方法可将上面的多条语句合成为一条,只用一次select即可实现多个时间段的查询,得到类似如下结果
列1 列2 列3
字段1 字段1 字段1
忘各位高人提供思路,谢谢
[解决办法]
行列转换
- SQL code
--行列互转--摘自中国风博客,引用请标明内容来源--1、行换列if object_id('Class') is not null drop table ClassGoCreate table Class([Student] nvarchar(2),[Course] nvarchar(2),[Score] int)Insert Classselect N'张三',N'语文',78 union allselect N'张三',N'数学',87 union allselect N'张三',N'英语',82 union allselect N'张三',N'物理',90 union allselect N'李四',N'语文',65 union allselect N'李四',N'数学',77 union allselect N'李四',N'英语',65 union allselect N'李四',N'物理',85 Go--2000方法:--动态:declare @s nvarchar(4000)set @s=''Select @s=@s+','+quotename([Course])+'=max(case when [Course]=' +quotename([Course],'''')+' then [Score] else 0 end)'from Class group by[Course]--select @sexec('select [Student]'+@s+' from Class group by [Student]')--生成静态:select [Student], [数学]=max(case when [Course]='数学' then [Score] else 0 end), [物理]=max(case when [Course]='物理' then [Score] else 0 end), [英语]=max(case when [Course]='英语' then [Score] else 0 end), [语文]=max(case when [Course]='语文' then [Score] else 0 end) from Class group by [Student]GO--动态:declare @s nvarchar(4000)Select @s=isnull(@s+',','')+quotename([Course]) from Class group by[Course]select @sexec('select * from Class pivot (max([Score]) for [Course] in('+@s+'))b')--生成静态:select * from Class pivot (max([Score]) for [Course] in([数学],[物理],[英语],[语文]))b--生成格式:/*Student 数学 物理 英语 语文------- ----------- ----------- ----------- -----------李四 77 85 65 65张三 87 90 82 78(2 行受影响)*/go--加上总成绩(学科平均分)--2000方法:--动态:declare @s nvarchar(4000)set @s=''Select @s=@s+','+quotename([Course])+'=max(case when [Course]='+quotename([Course],'''')+'then [Score] else 0 end)'from Class group by[Course]exec('select [Student]'+@s+',[总成绩]=sum([Score]) from Class group by [Student]')--加多一列(学科平均分用avg([Score]))生成动态:select [Student], [数学]=max(case when [Course]='数学' then [Score] else 0 end), [物理]=max(case when [Course]='物理' then [Score] else 0 end), [英语]=max(case when [Course]='英语' then [Score] else 0 end), [语文]=max(case when [Course]='语文' then [Score] else 0 end), [总成绩]=([Score]) --加多一列(学科平均分用avg([Score]))from Class group by [Student]go--2005方法:动态:declare @s nvarchar(4000)Select @s=isnull(@s+',','')+quotename([Course]) from Class group by[Course] --isnull(@s+',','') 去掉字符串@s中第一个逗号exec('select [Student],'+@s+',[总成绩] from (select *,[总成绩]=sum([Score])over(partition by [Student]) from Class) a pivot (max([Score]) for [Course] in('+@s+'))b ')--生成静态:select [Student],[数学],[物理],[英语],[语文],[总成绩] from (select *,[总成绩]=sum([Score])over(partition by [Student]) from Class) a --平均分时用avg([Score])pivot (max([Score]) for [Course] in([数学],[物理],[英语],[语文]))b 生成格式:/*Student 数学 物理 英语 语文 总成绩------- ----------- ----------- ----------- ----------- -----------李四 77 85 65 65 292张三 87 90 82 78 337(2 行受影响)*/go--2、列转行 if not object_id('Class') is null drop table ClassGoCreate table Class([Student] nvarchar(2),[数学] int,[物理] int,[英语] int,[语文] int)Insert Classselect N'李四',77,85,65,65 union allselect N'张三',87,90,82,78Go--2000:动态:declare @s nvarchar(4000)select @s=isnull(@s+' union all ','')+'select [Student],[Course]='+quotename(Name,'''')--isnull(@s+' union all ','') 去掉字符串@s中第一个union all+',[Score]='+quotename(Name)+' from Class'from syscolumns where ID=object_id('Class') and Name not in('Student')--排除不转换的列order by Colidexec('select * from ('+@s+')t order by [Student],[Course]')--增加一个排序生成静态:select * from (select [Student],[Course]='数学',[Score]=[数学] from Class union all select [Student],[Course]='物理',[Score]=[物理] from Class union all select [Student],[Course]='英语',[Score]=[英语] from Class union all select [Student],[Course]='语文',[Score]=[语文] from Class)t order by [Student],[Course]go--2005:动态:declare @s nvarchar(4000)select @s=isnull(@s+',','')+quotename(Name)from syscolumns where ID=object_id('Class') and Name not in('Student') order by Colidexec('select Student,[Course],[Score] from Class unpivot ([Score] for [Course] in('+@s+'))b')goselect Student,[Course],[Score] from Class unpivot ([Score] for [Course] in([数学],[物理],[英语],[语文]))b生成格式:/*Student Course Score------- ------- -----------李四 数学 77李四 物理 85李四 英语 65李四 语文 65张三 数学 87张三 物理 90张三 英语 82张三 语文 78*/
[解决办法]
请贴具体的测试数据和结果集看,看楼主表述的感觉像是行转列,但又有些不对。。。
[解决办法]
- SQL code
select max(case when time between 时间1 and 时间2 then 字段1 end) as 字段1, max(case when time between 时间3 and 时间4 then 字段1 end) as 字段1, max(case when time between 时间5 and 时间6 then 字段1 end) as 字段1from 表1where time between 时间1 and 时间6