"miquel_ibanez" <miquel_ibanez(at)sumimail(dot)com> writes:
> CREATE TYPE t_cod_t_activ AS (
> cod_t_activ CHAR(10)
> );
If you just want an alias for char(10), a domain would probably work
better. CREATE TYPE AS is meant for creating multi-field row types.
> Does it mean that I cannot create an index on a field wich is of a type
> defined by the user?
Sure, if you are also willing to define operators and operator classes
on your type.
regards, tom lane