Re: Trailing comma support in SELECT statements

On 10/03/2014 12:20 PM, Bruce Momjian wrote:
> On Sun, Sep 28, 2014 at 01:42:46PM +0200, Bogdan Pilch wrote:
>> Hi,
>> I have created a small patch to postgres source (in particular the
>> psql part of it) that accepts trailing comma at the end of list in
>> SELECT statement.
>>
>> The idea is to be able to say both (with the same result):
>> SELECT a, b, c from t;
>> SELECT a, b, c, from t;
>>
>> Attached you can find a patch containing regression test (incorporated
>> into the serial_schedule).
>> My patch is relative to origin/REL9_4_STABLE branch as that is the one
>> I started from.
>>
>> My plea is to have this change merged into the main stream so that it
>> becomes available in upcoming releases.
>>
>> This modification does not require any interaction with user.
>> It does not create any backward compatibility issues.
> Interesting --- I know some languages allow trailing delimiters, like
> Perl and Javascript.  Could this mask query errors?  Does any other
> database accept this?  Seems this would need to be done in many other
> places, like UPDATE, but let's first decide if we want this.
>
> FYI, it is usually better to discuss a feature before showing a patch.
>

Javascript might accept it, but it's not valid JSON.

The case for doing it is that then you can easily comment out any entry 
at all in a select list:
    select        foo as f1,        bar as f2,        -- baz as f3,    from blurfl


cheers

andrew