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Re: Proposed definition of ExprMultiSet

From: Steve Harris <steve.harris@garlik.com>
Date: Mon, 8 Mar 2010 17:30:20 +0000
Cc: SPARQL Working Group <public-rdf-dawg@w3.org>
Message-Id: <90DC5414-7043-42FA-887E-3A5CD9985C7B@garlik.com>
To: Andy Seaborne <andy.seaborne@talis.com>
On 8 Mar 2010, at 16:02, Andy Seaborne wrote:
...
>>> An alternative is,
>>>
>>> -----------
>>> | x | C |
>>> ===========
>>> | :x1 | 3 |
>>> | :x2 | 9 |
>>> | :x3 |   |
>>> | :x4 |   |
>>> -----------
>>>
>>> which retains the group row (to distinguish from no key).
>>
>> Yes, I wrote that first, then changed it. I think that the version  
>> with
>> the removed rows is closer to the rest of SPARQL, as error rows are
>> removed in (sub-)queries. It's also possible to prevent this, in many
>> cases at least, with creative use of COALESCE, but I know you're  
>> not a fan.
>
> FILTERs remove errors but SELECT expressions just don't bind that  
> slot if the expression fails.
>
> SELECT (1/0 AS ?v) {}
>
> is one row, no bindings as currently spec'ed.

Ah, OK, I missed that subtlety. In that case I'm fine with that  
behaviour.

- Steve

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Received on Monday, 8 March 2010 17:30:49 GMT

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