在多个变量中显示结果访问查询

Question

我有一系列5个变量（来自同一张表）。我希望通过查询向我展示参与者谁在至少有一个价值的变量。即，如果所有5个变量都是空白的，则不显示该参与者。我怎么能这样做呢？

SELECT [Patient Information].MRN, [Patient Information].[MRI_Results(1)], [Patient Information].[MRI_Results(2)], [Patient Information].[Blood_Results(Base)], [Patient Information].[Blood_Results(FU1)], [Patient Information].[Blood_Results(FU2)], [Patient Information].[Blood_Results(FU3)] 
FROM [Patient Information] 
ORDER BY [Patient Information].[MRI_Results(1)] DESC , [Patient Information].[MRI_Results(2)] DESC , [Patient Information].[Blood_Results(Base)] DESC , [Patient Information].[Blood_Results(FU1)] DESC , [Patient Information].[Blood_Results(FU2)] DESC , [Patient Information].[Blood_Results(FU3)] DESC; 

Answer 1

一个简单的“WHERE”子句可以解决这个问题。你只要有一个你想保留记录的值就可以使用OR运算符。

根据你的价值观是什么，你可能需要改变语法（即“不ISNULL（）”而不是“不为空”），所以这可能需要一些小的调整，但应该让你在正确的方向。

SELECT [Patient Information].MRN, [Patient Information].[MRI_Results(1)], 
     [Patient Information].[MRI_Results(2)], 
     [Patient Information].[Blood_Results(Base)], 
     [Patient Information].[Blood_Results(FU1)], 
     [Patient Information].[Blood_Results(FU2)], 
     [Patient Information].[Blood_Results(FU3)] 
FROM [Patient Information] 
WHERE [Patient Information].MRN IS NOT NULL 
    OR [Patient Information].[MRI_Results(1)] IS NOT NULL 
    OR [Patient Information].[MRI_Results(2)] IS NOT NULL 
    OR [Patient Information].[Blood_Results(Base)] IS NOT NULL 
    OR [Patient Information].[Blood_Results(FU1)] IS NOT NULL 
    OR [Patient Information].[Blood_Results(FU2)] IS NOT NULL 
    OR [Patient Information].[Blood_Results(FU3)] IS NOT NULL 

ORDER BY [Patient Information].[MRI_Results(1)] DESC , 
     [Patient Information].[MRI_Results(2)] DESC , 
     [Patient Information].[Blood_Results(Base)] DESC , 
     [Patient Information].[Blood_Results(FU1)] DESC , 
     [Patient Information].[Blood_Results(FU2)] DESC , 
     [Patient Information].[Blood_Results(FU3)] DESC;