Re: [HACKERS] Re: [QUESTIONS] is Postgres an SQL-based database?

> I agree with you Tom, PostgreSQL should be more than standard,
> but users expect that PostgreSQL at least supports SQL syntax.
> I agree with you if you talk about implement functions not supported by SQL
> but I can't understand if you write the same function with another syntax.

Well, one explanation is that sometimes I get it wrong :)

> PostgreSQL has many functions that doesn't follow SQL-standard syntax.
> I can understand this:
>
>   ROLLBACK [ WORK ]            -- SQL-syntax
>   rollback [transaction|work]  -- PostgreSQL-syntax (this is more than standard)
>
> and
>
>   ALTER TABLE <class_name>     ADD [COLUMN] <attr> <type>; --SQL
>   alter table <class_name> [*] add  column  <attr> <type>; --PostgreSQL
>
>   In this case [*] show that PostgreSQL is an ORDBMS,
>   but what about keyword COLUMN? It sould be optional.
>
> but I can't understand things like:
>
>   \connect <dbname|-> <user>                                    --PostgreSQL
> insted of:
>   CONNECT TO { DEFAULT | <SQL-server name>                      --SQL
>                   [ AS <connection name> ]
>                   [ USER <user name> ] }

Connections are done by the frontend, which does not parse the SQL. We could think about
implementing this if we allowed the backend to force a database change. Don't know if
this is easy or reasonably so.

>   CAST expression AS data-type                         --PostgreSQL
> insted of:
>   CAST ( expression AS { data-type | domain } )        --SQL

Wow, I never noticed that parens are in the syntax! Will look at changing it...

                                                   - Tom