Correct Answer: A
Explanation:
Scenario Overview:
The GIS data administrator is experiencing lag when changing the parameter value of a definition query.
Definition queries dynamically filter data based on attribute values. Slow performance often indicates inefficient attribute searches.
Solution: Add Attribute Index
An attribute index allows the database to quickly locate rows based on values in the indexed column, significantly improving query performance.
When definition queries rely on non-indexed fields, the database must scan the entire dataset to filter records, leading to noticeable delays.
By creating an attribute index on the fields used in the definition query, the database can optimize filtering, reducing lag.
(ArcGIS Documentation: Attribute Indexes)
Steps to Add Attribute Index:
In ArcGIS Pro, open the Attribute Indexes tool.
Select the feature class or table used in the definition query.
Specify the field(s) that the definition query is based on.
Click Run to create the index.
Alternative Options:
Option B: Add Spatial Index
Spatial indexes optimize spatial queries (e.g., finding features within an area). This does not address attribute-based definition query lag.
Option C: Recalculate Extent
Recalculating the extent corrects boundary discrepancies in spatial datasets but has no impact on attribute query performance.
Thus, adding an attribute index is the correct action to resolve lag in definition queries.
