Обсуждение: Variable number or arguments to a function possible?

Hello everybody,

Is it possible to create a function that can take a variable number of
arguments?
I would like to write a function that creates a new record in the
database. Based on what I send it, it should create a record in the
appropriate table.

Simple pseudo-code example:

... function create_record( varchar [,...] ) returns bigint as

if $1 = 'state' then insert into state ( $2, $3 ) // $2 being state
name, and $3 state code
if $1 = 'phone' then insert into phone ( $4::bigint, $2, $3 ) // $2 =
phone number, $3 = phone type, $4 = id of person that ownes the phone

and so on.

How would I declare that function?

Thanks.


best regards,
chris
--
chris ruprecht
database grunt and bit pusher extraordinaíre

Chris Ruprecht написа:
> Hello everybody,
> 
> Is it possible to create a function that can take a variable number of
> arguments?
> I would like to write a function that creates a new record in the
> database. Based on what I send it, it should create a record in the
> appropriate table.
> 
> Simple pseudo-code example:
> 
> ... function create_record( varchar [,...] ) returns bigint as
> 
> if $1 = 'state' then insert into state ( $2, $3 ) // $2 being state
> name, and $3 state code
> if $1 = 'phone' then insert into phone ( $4::bigint, $2, $3 ) // $2 =
> phone number, $3 = phone type, $4 = id of person that ownes the phone
> 
> and so on.
> 
> How would I declare that function?

You'll be able to do that (or something similar) in the next, still
in beta, version 8.4
(http://www.postgresql.org/docs/8.4/static/xfunc-sql.html#XFUNC-SQL-VARIADIC-FUNCTIONS),
but right now the closest to what you want is function overloading
(http://www.postgresql.org/docs/current/static/xfunc-overload.html).



-- 
Milen A. Radev

Chris Ruprecht <chris@ruprecht.org> writes:
> Is it possible to create a function that can take a variable number of  
> arguments?

No, but you can make it take an array and then write something like
myfunc(array[x, y, ...])

8.4 will have some syntactic sugar that looks like variable numbers of
arguments, but it's reducing to the above underneath.
        regards, tom lane