Re: Re: Changing the default value of an inherited column

Peter Eisentraut wrote:
>Tom Lane writes:
>
>> It seems that in pre-7.0 Postgres, this works:
>>
>> create table one(id int default 1, descr text);
>> create table two(id int default 2, tag text) inherits (one);
>>
>> with the net effect that table "two" has just one "id" column with
>> default value 2.
>
>Although the liberty to do anything you want seems appealing at first, I
>would think that allowing this is not correct from an OO point of view.

I don't agree; this is equivalent to redefinition of a feature (=method) in
a descendant class, which is perfectly acceptable so long as the feature's
signature (equivalent to column type) remains unchanged.

--
Oliver Elphick Oliver(dot)Elphick(at)lfix(dot)co(dot)uk
Isle of Wight http://www.lfix.co.uk/oliver
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