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From: Daniele Varrazzo <daniele.varrazzo@gmail.com>
Date: Thu, 4 Oct 2018 15:05:51 +0100
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Subject: Re: Plans for 2.8
To: Federico Di Gregorio <fog@dndg.it>
Cc: psycopg@lists.postgresql.org
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On Thu, Oct 4, 2018 at 2:27 PM Federico Di Gregorio <fog@dndg.it> wrote:
>
> On 10/04/2018 02:38 PM, Daniele Varrazzo wrote:
> > A tiny improvement to SQL generation is already ready^W merged in
> > #732: it will be possible to use `Identifier("schema", "name")` which
> > would be rendered in dotted notation in the query. Currently
> > `Identifier()` takes a single param so this extension is backward
> > compatible and there is no need to introduce a new `Composable` type
> > to represent dotted sequences of identifiers.
>
> I understand that from a compatibility point of view everything works
> with the "schema", "name" order of arguments (you just switch on the
> number of arguments) but usually such approach causes infinite headaches
> when you remove or add the namespace from the call.
>
> `Identifier(name, schema=None)` is better, IMHO because makes explicit
> that the mandatory and first argument is always the identifier itself,
> while the schema is optional.

"schema", "table" is only an example: it could be "table"."field",
even "schema"."table"."field", or "extension"."setting"... The object
only wants to represent a dotted sequence of identifiers, at lexical
level, nothing with semantics attached such as "an optionally
schema-qualified table name" or "a field name". If the object was
`Table()` or `Field()` rather than `Identifier()` I'd totally agree
with you.

-- Daniele