I want to test a [function-based **spatial** index](https://gis.stackexchange.com/a/92599/62572) using db<>fiddle for Oracle 18c.

In order to create the index, I need to create a record in Oracle Spatial's `USER_SDO_GEOM_METADATA` table (tehcnically, it's a view). 

The metadata record needs to include the function's schema/owner name: `my_owner.my_function(...)` —or— `mdsys.sdo_geometry(...)`, etc..

```
insert into user_sdo_geom_metadata (table_name, column_name, diminfo, srid)
values (
 'my_table', 
 'my_owner.my_function(shape)', -- 🡄 look here.
 sdo_dim_array (
  sdo_dim_element('X', 567471.222,  575329.362, 0.5),
  sdo_dim_element('Y', 4757654.961, 4769799.360, 0.5)
 ),
 26917
);
commit;
```
**Problem:**

In db<>fiddle, the owner/schema name seems to be **temporary**/system-generated:

    select sys_context( 'userenv', 'current_schema' ) from dual

    Result:
    SQL_WUOSPGUJBKKFTJGWOGLQNVMPC

https://dbfiddle.uk/?rdbms=oracle_18&fiddle=cf79a390e7594c075af1f380a49de598

So, the schema name changes every time hit the run button. If that's the case, then for **custom** functions, perhaps it doesn't make sense to enter the temporary schema name — since the schema name is always changing.

**Question:**

Does that make it impossible to test the function-based spatial index in db<>fiddle that uses a custom function? Or have I misunderstood?