Question

I’m attempting to get a list and definition of user defined functions within 3 different databases to combine into a single database.

I have the select statement that lists the 3 user defined functions but when I run it the ROUTINE_BODY column shows 'EXTERNAL' but EXTERNAL_NAME and EXTERNAL_LANGUAGE is NULL (as well as ROUTINE_DEFINITION which it should be for an EXTERNAL routine).

SELECT * 
FROM INFORMATION_SCHEMA.ROUTINES 
WHERE ROUTINE_TYPE = 'FUNCTION'  

This gives me back the database, routine name, everything I need except for the actual definition of the function. Can anyone help me with where SQL Server may be storing the SQL for the functions?

Answer 1

You need to use object_definition system function

select specific_name, object_definition(object_id(specific_name))
from INFORMATION_SCHEMA.ROUTINES 
where routine_type = 'FUNCTION' 

UPDATE: Ok, so it’s not what you want. I’ve just missed that you need definitions of CLR functions and not standard user defined functions.
Actually, I have a pair of script that can help you. You can get parameters of CLR function with them and then combine a scripts you need

select 
    O.[object_id] as System_Object_ID,
    A.Name as Assembly_Name,
    ASM.assembly_class as Assembly_Class,
    ASM.assembly_method as Assembly_Method,
    case
        when ASM.execute_as_principal_id is null then 'CALLER'
        else PR.name
    end as Execute_As_Name
from sys.assembly_modules as ASM with (nolock)
    inner join sys.assemblies as A with (nolock) on A.[assembly_id] = ASM.[assembly_id]
    inner join sys.objects as O with (nolock) on O.[object_id] = ASM.[object_id]
    left outer join sys.schemas as S with (nolock) on S.[schema_id] = O.[schema_id]
    left outer join sys.database_principals as PR on PR.principal_id = ASM.execute_as_principal_id

select 
    O.[object_id] as System_Object_ID,
    P.name as Parameter_Name,
    T.name as [Type_Name],
    P.precision as [Precision],
    P.scale as [Scale],
    P.max_length as [Max_Length],
    case
        when P.has_default_value = 1 then isnull(cast(P.default_value as nvarchar(max)), 'null')
        else null
    end as Default_Value,
    P.is_output as Is_Output
from sys.assembly_modules as ASM with (nolock)
    inner join sys.parameters as P with (nolock) on P.[object_id] = ASM.[object_id]
    inner join sys.objects as O with (nolock) on O.[object_id] = ASM.[object_id]
    left outer join sys.schemas as S with (nolock) on S.[schema_id] = O.[schema_id]
    inner join sys.types as T with (nolock) on T.system_type_id = P.system_type_id and T.user_type_id = P.user_type_id      

or, may be easier, you can just script that objects from SSMS 🙂