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When performing field aggregation in JQL Custom Charts, it's important to note that if a specific field is blank for certain issues, a corresponding blank line will appear in the JQL chart, indicating a count of 0 for that particular category.
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Reason
The field count shows displays 0 along with the a blank line because the null value is not equal to another null value, that’s why it does not get grouped in, due to the fact that issues in which the specific field lacks a value are considered as null. It's important to note that null values are not equivalent to one another, which results in them not being grouped together when the count of the category specific field is calculatedcomputed.
Steps for Resolution
A potential solution for this issue is to create two separate JQL custom charts. One chart can display all the issues where the specific field is blank, and the other chart can show all the issues where the specific field does not have a blank value. To achieve this, you can utilize the "is null" and "is not null" keywords in your JQL queries. This approach will help you segregate and analyze the data based on the presence or absence of values in the specific field.
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