Enhance ArcGIS functionality using ST_Geometry
If you store your data in the geodatabase using ST_Geometry spatial types, you can use SQL in addition to ArcGIS Desktop to work with your data. For example, you can use SQL to add records to an existing feature class or apply a definition query using SQL to display only features that meet specific criteria.
Specific examples of using SQL with existing feature classes can be seen in Workflow: Using SQL with existing feature classes.
If the owner of a dataset stored in Oracle changes the dataset schema using SQL, such as adding a field or redefining a field length, that user must open the dataset in ArcGIS Desktop to update the information in the system tables. If the owner does not do this, the next time another user tries to view the data, he or she will get a permissions error and will not be able to access the data.