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Thread: CREATE TYPE function examples

CREATE TYPE function examples

From
Roberto Mello
Date:
I'm looking for some examples of how the functions for CREATE TYPE
should be. There are none in the documentation, so I was hoping to find
someone here that could help me.For example, the documentation has this example:

CREATE TYPE box (INTERNALLENGTH = 8,   INPUT = my_procedure_1, OUTPUT = my_procedure_2); 
What would the functions my_procedure_1 and my_procedure_2 look like?
Thanks,
-Roberto 
-- 
+----| http://fslc.usu.edu USU Free Software & GNU/Linux Club |------+ Roberto Mello - Computer Science, USU -
http://www.brasileiro.net      http://www.sdl.usu.edu - Space Dynamics Lab, Developer    
 
YES!!  eh, NO!!! oh, well  MAYBE!!!!!!!!

Re: CREATE TYPE function examples

From
Peter Eisentraut
Date:
Roberto Mello writes:

>     I'm looking for some examples of how the functions for CREATE TYPE
> should be. There are none in the documentation, so I was hoping to find
> someone here that could help me.

http://www.ca.postgresql.org/users-lounge/docs/7.1/postgres/xtypes.html

This seems to be outdated regarding the fmgr update, though.  (Hint,
hint...)

-- 
Peter Eisentraut   peter_e@gmx.net   http://funkturm.homeip.net/~peter

Re: CREATE TYPE function examples

From
Roberto Mello
Date:
On Tue, Jul 10, 2001 at 06:43:59PM +0200, Peter Eisentraut wrote:
> 
> http://www.ca.postgresql.org/users-lounge/docs/7.1/postgres/xtypes.html
Oh. So you have to write a function in C to use CREATE TYPE?

> This seems to be outdated regarding the fmgr update, though.  (Hint,
> hint...)
How so? Would you please elaborate? I'm note familiar with the update.
-Roberto    
-- 
+----| http://fslc.usu.edu USU Free Software & GNU/Linux Club |------+ Roberto Mello - Computer Science, USU -
http://www.brasileiro.net      http://www.sdl.usu.edu - Space Dynamics Lab, Developer    
 
Politically correct?  I'm not even ANATOMICALLY correct!

Re: CREATE TYPE function examples

From
Tom Lane
Date:
Roberto Mello <rmello@cc.usu.edu> writes:
> What would the functions my_procedure_1 and my_procedure_2 look like?

src/backend/utils/adt/ is full of examples of datatype I/O procedures.
Pick an existing type that does something vaguely like your type
(at the very least pick one that uses the same kind of representation:
pass-by-value, fixed-length pass-by-reference, or variable-length),
and use its code as a model.

The only thing you need to do differently in dynamically loaded C code
than is done in the main sources is to declare version-1 calling
convention functions with PG_FUNCTION_INFO_V1().  This is assumed for
builtin functions as of 7.1, but the default for dynamically loaded
functions is to assume old-style calling conventions.
        regards, tom lane