Composite Type : pros and cons

[Leguevaques Alex <alex.leguevaques@xxxxxxxxxx>]

Hello,

I'm new to Pg and exploring its advanced functionalities for a project.

I find composite type very interesting, but what are problems/limitations ?

I'd want to create this structure for example: 

Phone

Nom du champ	Type	Accès	Clef	Commentaire
typ_tel	integer			type téléphone (liste  25)
tel_pre	varchar(5)			Préfixe international téléphone
tel_num	varchar(14)
tel_ext	varchar(5)			Numéro de poste

and other structures for address and timestamp fields (creation and update timestamps.

Is it a good idea ? Are index, constraints possible/easy on subfields ?

Thank you