SQL Server 2008 - 查询以获得分数格式的结果

Question

我有一个包含这样的数据的表:

MinFormat(int)  MaxFormat(int)  Precision(nvarchar)
   -2              3             1/2

精度值只能是1/2,1/4,1/8,1/16,1/32,1/64.

现在我想要查询结果为 -

 -2
 -3/2 
 -1 
 -1/2 
  0 
  1/2 
  1 
  3/2  
  2 
  5/2 
  3

任何获得结果的查询如下？

想法是根据精度值创建基于最小边界(MinFomrat col值为整数)到最大边界(MaxFormat Col值为整数)的结果.

因此,在上面的示例中,值应从-2开始,并根据精度值(1/2)生成下一个值,直到达到3

Answer 1

请注意,这仅适用于Precision 1/1,1/2,1/4,1/8,1/16,1/32和1/64

DECLARE @t table(MinFormat int, MaxFormat int, Precision varchar(4))
INSERT @t values(-2, 3, '1/2')

DECLARE @numerator INT, @denominator DECIMAL(9,7)
DECLARE @MinFormat INT, @MaxFormat INT

-- put a where clause on this to get the needed row

SELECT @numerator   = 1,
       @denominator = STUFF(Precision, 1, charindex('/', Precision), ''),
       @MinFormat = MinFormat,
       @MaxFormat = MaxFormat
FROM @t


;WITH N(N)AS 
(SELECT 1 FROM(VALUES(1),(1),(1),(1),(1),(1),(1),(1),(1),(1))M(N)),
tally(N)AS(SELECT ROW_NUMBER()OVER(ORDER BY N.N)FROM N,N a,N b,N c,N d,N e,N f)
SELECT top(cast((@MaxFormat- @MinFormat)  / (@numerator/@denominator) as int) + 1) 
CASE WHEN val % 1 = 0 THEN cast(cast(val as int) as varchar(10))
     WHEN val*2 % 1 = 0 THEN cast(cast(val*2 as int) as varchar(10)) + '/2'
     WHEN val*4 % 1 = 0 THEN cast(cast(val*4 as int) as varchar(10)) + '/4'
     WHEN val*8 % 1 = 0 THEN  cast(cast(val*8 as int) as varchar(10)) + '/8'
     WHEN val*16 % 1 = 0 THEN cast(cast(val*16 as int) as varchar(10)) + '/16'
     WHEN val*32 % 1 = 0 THEN cast(cast(val*32 as int) as varchar(10)) + '/32'
     WHEN val*64 % 1 = 0 THEN cast(cast(val*64 as int) as varchar(10)) + '/64'
END
FROM tally
CROSS APPLY
(SELECT @MinFormat +(N-1) *(@numerator/@denominator) val) x