Is is "bad" not to set the Priority of an Issue Type?

[Paul Webber]

In configuring a new Issue Type it was requested to hide the Priority Field. This can be done in the Field Configuration. 

Now when I query those issues based upon Priority the set is empty. For example "and priority not in (High, Highest, Low, Lowest, Medium)". The opposite is true also "in" as opposed to "not in"; "is empty" also returns an empty set.

On the Backlog view the icons are not present whereas with other Issue Types the icons are present. 

The Priority value is not there even after I "show" the Field on the Field Configuration.

When using the "Where is my field?" function it gives a hint: "The field 'Priority' does not have value for issue PP-1861 and will not be displayed on the view issue page. Set value for that field so that it shows up"

So it seems that the new Issue Type instance with the hidden Priority does not have a Priority value set. And you can not query for it based upon the Priority not being set. 

Will this lead to data integrity issues in the future?

Using JIRA server 7.8.2

[Nic Brough -Adaptavist-]

No.  It's fine to run a project without any priority on the issues.  It won't cause you problems in the future, unless there's some radical change in Jira (and then I'd expect the upgrade path to include code to set it to a default)

You should be able to search for issues though.  "Priority is empty" should return all the ones with no priority.