在动态数据透视表SQL查询中替换空值

Question

图像转录：

FTE/RATE CARD | 2018-01-01 | 2018-02-01 | 2018-03-01 | 2018-04-01 | 2018-05-01 | 2018-06-01 | ...
-------------------------------------------------------------------------------------------------
FTE 3         | NULL       | NULL       | NULL       | 33         | 38         | 40.5       | ...

我有一个枢轴sql查询，如下所示。 我需要在结果中将NULL值替换为零。 我不知道在查询中应在哪里使用IsNull或Coalesce函数。

DECLARE @cols AS NVARCHAR(MAX),
        @query AS NVARCHAR(MAX) 
SELECT  @cols = STUFF
(
(
SELECT distinct ',' + QUOTENAME([MONTH])
FROM   [HEADCOUNT]
WHERE  [MONTH] BETWEEN '01-012018' AND '12-01-2018'
ORDER BY ',' + QUOTENAME([MONTH])
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'),1,1,''
)
SET     @query = 'SELECT [FTE/RATE CARD],' + @cols + ' FROM
(
SELECT  [MONTH],[FTE/RATE CARD],[HC]
FROM    [HEADCOUNT]
WHERE   [CC-LOC] IN ([CC-LOC]) 

) x pivot (Sum ([HC]) for [MONTH] in (' + @cols + '))p' execute(@query)

Answer 1

您将需要为select语句生成另一个列列表，并使用ISNULL包装各个月份，如下所示：

DECLARE @cols AS NVARCHAR(MAX),
        @selectCols AS NVARCHAR(MAX),
        @query AS NVARCHAR(MAX) 

SELECT  @selectCols = STUFF
(
(
SELECT distinct ', ISNULL(' + QUOTENAME([MONTH]) + ', 0) AS ' + QUOTENAME([MONTH])
FROM   [HEADCOUNT]
WHERE  [MONTH] BETWEEN '01-012018' AND '12-01-2018'
ORDER BY ',' + QUOTENAME([MONTH])
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'),1,1,''
)



SELECT  @cols = STUFF
(
(
SELECT distinct ',' + QUOTENAME([MONTH])
FROM   [HEADCOUNT]
WHERE  [MONTH] BETWEEN '01-012018' AND '12-01-2018'
ORDER BY ',' + QUOTENAME([MONTH])
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'),1,1,''
)
SET     @query = 'SELECT [FTE/RATE CARD],' + @selectCols + ' FROM
(
SELECT  [MONTH],[FTE/RATE CARD],[HC]
FROM    [HEADCOUNT]
WHERE   [CC-LOC] IN ([CC-LOC]) 

) x pivot (Sum ([HC]) for [MONTH] in (' + @cols + '))p' execute(@query)