Clear all registered functions.
Clear all registered functions.
Create a copy of this registry with identical functions as this registry.
Create a copy of this registry with identical functions as this registry.
Drop a function and return whether the function existed.
Drop a function and return whether the function existed.
Checks if a function with a given name exists.
Checks if a function with a given name exists.
A trivial catalog that returns an error when a function is requested. Used for testing when all functions are already filled in and the analyzer needs only to resolve attribute references.