访问查询但没有返回结果

Question

我在Access中有一个查询,并想知道是否可以使用该where not exists子句在没有返回的行时显示每个字段的特定文本.

示例查询:

Select Field1, Field2, Field3  
From TableA  
Where Field1 = "test";

如果没有返回结果,我希望以下内容返回:

Field1 = "test"  
Field2 = "not provided"  
Field2 = "not provided"  

Answer 1

怎么样:

SELECT Field1, Field2
FROM Table
WHERE ID=3
UNION ALL SELECT DISTINCT "None","None" FROM AnyTableithAtLeastOneRow
WHERE 3 NOT IN (SELECT ID FROM Table)