Re: processSQLNamePattern() analog

Sergey Cherkashin <s(dot)cherkashin(at)postgrespro(dot)ru> writes:
> The command "\dA" (as well as several commands that I write) accept the access method name template. The resulting template is processed by the processSQLNamePattern () function, which means that a template with a schema can be fed to the input. But since the access method does not have schema, it's needed to handle somehow a command like "\dA foo. *". At this point, the command will display a full list of access methods, not paying attention to the presence of the schema name in the template.

I don't see a particular problem with this. The \d commands in general
are meant to accept handwritten input, so they should err on the side
of being forgiving. I do not see how it would be an improvement to
throw an error complaining that the pattern shouldn't have been
schema-qualified for this particular type of name, nor would the
alternative possibility that "*.*" silently refuses to match anything
be a great idea.

Also, there are cases like \dd where the same name pattern is applied to
multiple kinds of objects. (I'm not sure if that particular command
covers both schema-qualified and not-schema-qualified objects today,
but surely it might in future.) So being picky would definitely not work
well for that.

> I also need a possibility to handle templates of type "schema.table.column",

Why? I think you'd be best off not going there, because it will
create confusion against the SQL-standard-mandated possibility of
"database.schema.table". We don't really support that notation
today in most contexts, but it might be a problem in future.

regards, tom lane