Histogram: handle null valued data on Transaction Edge and Link statistics.

[OrionsGuardian]

Prerequisites

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Description of the Change

Histogram can now perform Sum, Average, Min, and Max function on Link and Edge Transaction attributes that are defined as nullable numeric data fields.

Alternate Designs

Why Should This Be In Core?

Enhancement

Benefits

Provides functionality to larger data sets.

Possible Drawbacks

There may be cases where a user would prefer a null value to be treated as a value of 0.
But doing so would affect min, max, and average calculations.

Verification Process

Create 2 nodes
Create 4 transactions between them
Set your connection type to Transactions (Display -> Connection Types -> Transactions)
Select 1 transaction and define a custom attribute "LongNullTest" of type long_or_null
Set a value of 10 in that attribute
Select another transaction and set the LongNullTest value to 20
The remaining two transaction should still have null values by default.
Open the Histogram View
Set the Graph Element to "Link".
Set the Category to "Average Transaction Attribute"
Set the Property to "LongNullTest"

Confirm the Histogram now contain a data entry with a correct Property Value of 15.

Test again with the other Categories:
"Sum Transaction Attribute" (correct value should be 30)
"Maximum Transaction Attribute" (correct value should be 20)
"Minimum Transaction Attribute" (correct value should be 10)

Then test again with a mix of transactions going in both directions between two nodes.
and setting the Histogram Graph Element to "Edge"

Applicable Issues

#2260

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
89.3% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud