>The execution plan indicates a Key Loookup 66% process on the object which is my primary key. However, the output list shows 8 fields. Is this 66% that CPU intensive because I did not include those 8 fields in the index definition?
Well, if you include these fields in the index, the query will perform better but your DML operations will take more time.
If it's not broken, fix it until it is.
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