Re: ecmascript 5 DATESTYLE

Pavel Stehule wrote:
> 2010/5/19 Peter Eisentraut <peter_e@gmx.net>:
>   
>> On tis, 2010-05-18 at 18:26 -0400, Ben Hockey wrote:
>>     
>>> ecmascript 5 is the most recent specification for JavaScript and i
>>> would think that having a DATESTYLE format to simplify
>>> interoperability with JavaScript applications would be highly
>>> desirable.
>>>       
>> Note that we haven't got any other datestyles that are intended to
>> support interoperability with some language.  It is usually the job of
>> the client driver to convert PostgreSQL data (plural of datum) to the
>> appropriate type and format for the client environment or language.  Is
>> there any reason why JavaScript would be different?
>>     

I wouldn't be keen to see dedicated language specific handling of 
date/datetime formats. It would lead to an explosion of functions with 
new languages needing adding as and when their users jumped up and down 
on us. However a generic format could be very useful and would give the 
opportunity for people who need a language specific short cut the 
opportunity to do a CREATE FUNCTION wrapping the generic one with a hard 
coded format specifier.

Other platforms have generic support for this kind of task, for example 
SQLServer: http://msdn.microsoft.com/en-us/library/ms187928.aspx. I 
wouldn't recommend the SQLServer way, I think numeric format specifiers 
are clumsy. Perhaps a mechanism like Java which is nicely summarized 
here: 
http://java.sun.com/j2se/1.5.0/docs/api/java/text/SimpleDateFormat.html

Pavel: Why do you believe a generic format function would lead to SQL 
injections attacks?

> JavaScript isn't special language, but JSON is wide used format for
> interoperability. And same is true for XML datestyle format.
>
> Regards
> Pavel
>   

I think that the postgres handling of those data types should handle the 
date encoding themselves. For example, a XMLELEMENT call that was passed 
a date would format the date string to the xs:date format (e.g. 
2010-05-19) and when passed a timestamp format to xs:datetime (e.g. 
2010-05-19T09:29:52+01:00). I would see the JSON handling as being no 
different.

Thanks,

-- 
Mike Fowler
Registered Linux user: 379787

"I could be a genius if I just put my mind to it, and I,
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