I am using Firebird 4.0 Beta 1. The release notes describe a new system function RDB$ERROR:

"The function RDB$ERROR() takes a PSQL error context as input and returns the specific context of the active

exception. Its scope is confined to the context of the exception-handling block in PSQL. Outside the exception
handling block, RDB$ERROR always returns NULL"

 To test this in iSQL I have tried: select rdb$error(gdscode) from rdb$database

This results in:

Statement failed, SQLSTATE = 42000

Dynamic SQL Error

-SQL error code = -104

-Token unknown

-GDSCODE

I was expecting NULL to be returned. Have I misunderstood?