Why in JQL not equal value does not return fields that are empty?

[Sorin Sbarnea (Citrix)]

One of my users raised this question: 

• If you do project = A and fixVersion = 1.0 you get X issues.
• If you do project = A and fixVersion != 1.0 you get Y issues
• Now X+Y is not the total number of issues in project A

I explained him that he can test for empty values using fixVersion IS EMPTY but he correctly pointed that the real-life scenario is with much more complex filters and this limitation does makes them much more complex.

Any workarounds? Is this a bug or is by design?

[Nic Brough -Adaptavist-]

"does not equal" is not the same as "is empty".  Two points - first, the field may not be valid for an issue, and second, version is multi-select.  So your project could have

Issue 1:  No fix version

Issue 2:  Fix version = 1.0

Issue 3:  Fix version is not a valid field

Issue 4:  Fix version = 1.0 and 1.1

[Ollie Guan]

some issue fixversion is empty

you can try like this query

 (project = A and fixVersion != 1.0) and (project = A and fixVersion is empty)