Question

我在SQL中做了一些复杂的数学运算：

Select CAST((CAST(((COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108) <= '12:59' AND CLOSE_BY <> '' AND CONVERT(varchar(5), closedate, 108) <= '15:00' THEN CLOSE_BY ELSE NULL END) * 100)/nullif(COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108) <= '12:59' THEN ReportDate ELSE NULL END),0)) as decimal(18,2))+ 
CAST(((COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108) between '13:00' and '14:59' AND CLOSE_BY <> '' AND CONVERT(varchar(5), closedate, 108) <= '17:00' THEN CLOSE_BY ELSE NULL END) * 100)/nullif(COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108) between '13:00' and '14:59' THEN ReportDate ELSE NULL END),0)) as decimal(18,2))+
CAST(((COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108) between '15:00' and '16:59' AND CLOSE_BY <> '' AND CONVERT(varchar(5), closedate, 108) <= '19:00' THEN CLOSE_BY ELSE NULL END) * 100)/nullif(COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108) between '15:00' and '16:59' THEN ReportDate ELSE NULL END),0)) as decimal(18,2))+ 
CAST(((COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108) between '17:00' and '18:59' AND CLOSE_BY <> '' AND CONVERT(varchar(5), closedate, 108) <= '21:00' THEN CLOSE_BY ELSE NULL END) * 100)/nullif(COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108) between '17:00' and '18:59' THEN ReportDate ELSE NULL END),0)) as decimal(18,2))+ 
CAST(((COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108)  >= '19:00' AND CLOSE_BY <> '' AND CONVERT(varchar(5), closedate, 108)  <= '23:59'  THEN CLOSE_BY ELSE NULL END) * 100)/nullif(COUNT(CASE WHEN CONVERT(varchar(5), ReportDate, 108) >= '18:00'  THEN ReportDate ELSE NULL END),0)) as decimal(18,2))) / 5  as decimal(18,2)) as Avg,  
 getdate() as generatedate FROM WO  
 WHERE contractor is not null and 
 contractor <> 'SYSTEM DEFAULT' and LEFT(SCA,1)<>'L' and LEFT(SCA,1)<>' '  
 and SCH_DATE between ( SELECT CONVERT(DATE , GETDATE() , 103)) and ( SELECT CONVERT(DATE , GETDATE() , 103))  GROUP BY CONTRACTOR,Branch order by CONTRACTOR asc

某些值具有Null值，因此添加将不起作用，并且它变为null。我想仍然处理添加而不使null为0，是否可能？

Answer 1

NULL上的算术运算返回NULL，因此如果要返回值并忽略NULL，则必须将NULL替换为0.使用ISNULL标准SQL函数（example: ISNULL(<expression>, 0)）可以用0替换NULL。

使用带有空值的SQL执行一些加法函数，而不使其为0

1 个答案: