SPL routine executable format stored in UDR cache

The first time that a user executes an SPL routine, the database server stores the executable format and any query plans in the UDR cache in the virtual portion of shared memory.

When another user executes an SPL routine, the database server first checks the UDR cache. SPL execution performance improves when the database server can execute the SPL routine from the UDR cache. The UDR cache also stores UDRs, user-defined aggregates, and extended data types definitions.