Would it help to pass the results of the ChangeDetector to a StatisticsCalculator? Group by fme_db_operation, calculate the Total Count. Then you can see the number of INSERT and UNCHANGED (and DELETED) features, and proceed from there.

I did but no success

Unchanged features have value '<Missing>' in fme_db_operation.

okay, what about when there is no insert and only unchanged? so when only unchanged then the script will not run only when insert or Insert and Unchanged

Maybe you can do something with the NoFeaturesTester (from FME Hub).

again this unchanged will trigger every time and truncate the table and add values each time when workspace run

as you can see there is no insert value and now whenever this run its insert the values in database

Maybe I'm missing the point, but check your writer and make sure you're not dropping or truncating the table...

Nowhere in this workspace do I truncate a database table or add values.

You wanted to know when there are only inserted featurers, or when there are only unchanged features, or when there is a combination of inserted features and unchanged features.

The four Junctions give you exactly that. Now you can add whatever logic you want after each of the four Junctions, or combinations of Junctions.

which workspce

The image of a workspace in my above post.

can you share the workspce

See the attached workspace.

I emulated the table data and the update in two Creators. You can change the values in the creator by right-clicking Data, choosing Edit Attribute, and editing Value.