SQL十进制转换答案

【问题标题】：SQL decimal conversionSQL十进制转换
【发布时间】：2013-03-22 03:42:54
【问题描述】：

我在转换这个十进制值时遇到了一些问题，如下所示：

21.6080402010050

谁能帮我把它转换成21.6？

我试过这个，但它不起作用。

(convert(decimal(10, 2), SUM(t1.TOTAL))

这是查询

SELECT 
    t1.LINE_NO, t1.E_FIELD, t1.F_FIELD, t1.G_FIELD, t1.HSA_STATUS, 
    t1.FAMILY, t1.CACHE_FAMILY, 
    SUM(t1.TOTAL) AS CountOfLineNo, t2.TotalOfLineNo, 
    (convert(decimal(8,1), SUM(t1.TOTAL)) * 100 / t2.TotalOfLineNo ) AS Percentage
FROM (
    SELECT 
        LINE_NO, E_FIELD,F_FIELD,G_FIELD,HSA_STATUS,FAMILY,CACHE_FAMILY, 
        Count(LINE_NO) as Total
    FROM TX_HSA_SUMM
    WHERE MT_TIMESTAMP2 BETWEEN ('2013-03-07 10:10:00') AND ('2013-03-08 10:20:00')
    GROUP BY LINE_NO, E_FIELD, F_FIELD, G_FIELD, HSA_STATUS, FAMILY, CACHE_FAMILY) AS t1 
LEFT JOIN (
      SELECT LINE_NO, COUNT(LINE_NO) AS TotalOfLineNo
      FROM TX_HSA_SUMM
      WHERE MT_TIMESTAMP2 BETWEEN ('2013-03-07 10:10:00') AND ('2013-03-08 10:20:00')
      GROUP BY LINE_NO) AS t2 ON t1.LINE_NO = t2.LINE_NO
GROUP BY 
   t1.LINE_NO, t1.E_FIELD, t1.F_FIELD, t1.G_FIELD, t1.HSA_STATUS, t1.FAMILY, 
   t1.CACHE_FAMILY, t1.Total, t2.TotalOfLineNo
ORDER BY 
   t1.LINE_NO, t1.E_FIELD, t1.F_FIELD, t1.G_FIELD, t1.HSA_STATUS, t1.FAMILY, 
   t1.CACHE_FAMILY, t1.Total, t2.TotalOfLineNo

输出是

LINE_NO E_FIELD F_FIELD G_FIELD HSA_STATUS FAMILY CACHE_FAMILY CountOfLineNo    TotalOfLineNo   Percentage
23053B  00000   00000   00000   S   SUMMIT  WER 43  199 21.608040201005%

【问题讨论】：

你用的是什么数据库引擎？

标签： sql sql-server decimal

【解决方案1】：

请尝试以下查询

SELECT t1.LINE_NO, t1.E_FIELD, t1.F_FIELD, t1.G_FIELD, t1.HSA_STATUS, t1.FAMILY, t1.CACHE_FAMILY, 
    SUM(t1.TOTAL) AS CountOfLineNo, t2.TotalOfLineNo, convert(decimal(18,1),(convert(decimal(8,1),SUM(t1.TOTAL)) * 100 / t2.TotalOfLineNo)) AS Percentage
    FROM (
          SELECT LINE_NO, E_FIELD,F_FIELD,G_FIELD,HSA_STATUS,FAMILY,CACHE_FAMILY, Count(LINE_NO) as Total
          FROM TX_HSA_SUMM
          WHERE MT_TIMESTAMP2 BETWEEN ('2013-03-07 10:10:00') AND ('2013-03-08 10:20:00')
          GROUP BY LINE_NO,E_FIELD,F_FIELD,G_FIELD,HSA_STATUS,FAMILY,CACHE_FAMILY
        ) AS t1 
    LEFT JOIN (
          SELECT LINE_NO, COUNT(LINE_NO) AS TotalOfLineNo
          FROM TX_HSA_SUMM
          WHERE MT_TIMESTAMP2 BETWEEN ('2013-03-07 10:10:00') AND ('2013-03-08 10:20:00')
          GROUP BY LINE_NO
          ) AS t2 
      ON t1.LINE_NO = t2.LINE_NO
    GROUP BY t1.LINE_NO, t1.E_FIELD, t1.F_FIELD, t1.G_FIELD, t1.HSA_STATUS, t1.FAMILY, t1.CACHE_FAMILY, t1.Total,t2.TotalOfLineNo
    ORDER BY t1.LINE_NO, t1.E_FIELD, t1.F_FIELD, t1.G_FIELD, t1.HSA_STATUS, t1.FAMILY, t1.CACHE_FAMILY, t1.Total,t2.TotalOfLineNo

【讨论】：

【解决方案2】：

使用Round函数

select round(21.6080402010050,1)

【讨论】：

【解决方案3】：

看看ROUND 函数。

select round(21.6080402010050, 1)

适用于 MS SQL Server 或 MySQL

【讨论】：

我也试过了。因为实际上有相当多的行。以上是一些选择查询执行后的输出
返回多少行并不重要。下面的工作吗？ round((convert(decimal(8,1),SUM(t1.TOTAL)) * 100 / t2.TotalOfLineNo ), 1) AS Percentage

【解决方案4】：

这应该适合你：

SELECT ROUND(21.6080402010050,1)

SQL Fiddle Demo

它应该适用于大多数 RDBMS。

您的编辑：

ROUND((convert(decimal(8,1),SUM(t1.TOTAL)) * 100 / t2.TotalOfLineNo ),1)

【讨论】：