Re: [PATCH] Add XMLEXISTS function from the SQL/XML standard

Peter Eisentraut wrote:
> On ons, 2010-05-26 at 11:47 +0100, Mike Fowler wrote:
>   
>>> The XMLEXISTS function works with XQuery expressions and doesn't have
>>> the call signature that your patch implements
>>>       
>> Looking at the manuals of Oracle, Derby and DB2 I see how the call 
>> signature differs. I also note that Oracle's implementation is XPath 
>> only, Derby's is partial XQuery and DB2 appears to be full XQuery.
>>
>> What do people prefer me to do? I see the options as:
>>
>> 1) Change the call signature to match the standard
>> 2) Change the function name back to xpath_exists
>>     
>
> It would be nice to make XMLEXISTS work as in the standard, seeing how
> many others are providing the same interface.
>
>   
>> Should option one be the more popular there's further choices:
>>
>> 1) Integrate XQuery support to completely match the standard, however 
>> this will require the addition of a new library libxquery
>> 2) Leave the XPath as is, inline with Oracle's implementation
>> 3) Hybrid approach. Since XML is a comple time option, add XQuery as 
>> another. Conditional completion gives the full XQuery support when 
>> available or just the XPath when not
>>     
>
> I think providing XPath is enough, at least for now

Agreed. I'll get another patch together in the next day or two.

Regards,

-- 
Mike Fowler
Registered Linux user: 379787