When experiencing slow performance on a query of an indexed attribute in a large feature class within an enterprise geodatabase, and a SQL trace reveals that the attribute index is not being utilized despite the attribute values having a high degree of uniqueness and the delta tables containing few rows, the appropriate action is to rebuild the indexes.
Understanding Indexes in Enterprise Geodatabases:
Indexes are critical for enhancing query performance in databases. They allow the database management system (DBMS) to locate and retrieve data efficiently. Over time, as data is inserted, updated, or deleted, indexes can become fragmented or outdated, leading to suboptimal query performance.
ARCGIS PRO
Rebuilding Indexes:
The Rebuild Indexes tool in ArcGIS Pro is designed to rebuild existing attribute or spatial indexes in enterprise geodatabases. This process reorganizes the index structure, ensuring that the DBMS can effectively utilize the indexes during query execution.
ARCGIS PRO
Steps to Rebuild Indexes:
Access the Rebuild Indexes Tool:
In ArcGIS Pro, navigate to the Analysis tab and click on Tools.
In the Geoprocessing pane, search for and select the Rebuild Indexes tool.
Configure the Tool Parameters:
Input Database Connection: Specify the connection to your enterprise geodatabase.
Include System Tables: Decide whether to include system tables in the rebuild process. Including system tables can help maintain the overall health of the geodatabase but may increase processing time.
Execute the Tool:
Click Run to initiate the index rebuilding process. Monitor the progress and ensure the process completes without errors.
Alternative Options:
Compress Geodatabase: The Compress operation reduces the size of the geodatabase by removing redundant states and versions. While it can improve performance, it doesn't directly address index fragmentation.
Analyze Datasets: The Analyze Datasets tool updates database statistics, which helps the DBMS optimize query execution plans. However, if indexes are fragmented, analyzing datasets alone may not resolve performance issues.
Given the symptoms described—specifically, the attribute index not being used in queries—the most effective solution is to rebuild the indexes to ensure they are properly structured and utilized by the DBMS during query execution.
