Converting an Integer to Enum in PostgreSQL

Question

I have created a custom data type enum like so:

create type \"bnfunctionstype\" as enum ( 
    \'normal\', 
    \'library\', 
    \'import\', 
    \'thunk\', 
           


        

Answer 1

create function bnfunctionstype_from_number(int)
    returns bnfunctionstype
    immutable strict language sql as
$$
    select case ?
        when 0 then 'normal'
        when 1 then 'library'
        when 2 then 'import'
        when 3 then 'thunk'
        when 4 then 'adjustor_thunk'
        else null
    end
$$;