What is the purpose of the geodatabase repository table SPATIAL_REFERENCES?

The table contains information about the coordinate systems used within the geodatabase. It includes details such as the spatial reference ID (SRID), which is essential for defining how spatial data is displayed.

The table is automatically populated when spatial data with a spatial reference not already stored in the table is added to the geodatabase, ensuring that all spatial references are tracked and managed effectively.

New rows may be inserted and a new SRID generated in the following scenarios:

• Copying or importing feature classes into the geodatabase.
• Registering spatial data with the geodatabase.
• Defining a projection or coordinate system. 

6 key attributes make up the spatial reference record:

• SRID
• SRID Text
• Enable M
• Enable Z
• XY Tolerance
• XY Resolution

For the above scenarios, if any one of the attributes differs from the existing spatial references stored in the table a new record will be inserted, even when using the same spatial reference.

When creating or managing spatial data, the spatial reference system must exist in the SPATIAL_REFERENCES table. This ensures that the data aligns correctly with other spatial datasets.

Deleting all the spatial data that uses a particular spatial reference will not delete the spatial reference entry from the SPATIAL_REFERENCES table.