oqgraph-dev team mailing list archive

[Andrew McDonnell <bugs@xxxxxxxxxxxxxxxxxxx>]

Hi Arjen,

Hopefully I'll be able to tie up some of these loose ends this week, work
permitting

--Andrew




On 03/06/13 08:50, Arjen Lentz wrote:
> Hi Andrew
> 
>> The current behaviour always returns an empty set if the latch is NULL
>> should this be changed then?
> 
> v2 allowed latch to be NULL, so we should probably keep that.
> I don't see any reason to handle NULL and 0 differently though.
> 
> 
>> No latch specified seems to work correctly as you specify:
>> - or should it not have the latch, seq, linkid columns?
> 
> The below looks ok. Please ensure there are tests for each permutation in the basic test.
> Perhaps we should create a no-search test as the basic test already checks schema foo which is really basic.
> 
> You can't leave columns out as they're part of the schema. You can't half a row in an RDBMS.
> Resultsets should always be relationally consistent - the server core will actually enforce this because as you know it always applies its own filters even if the engine doesn't.
> 
> They are NULL because there is no WHERE clause on them specifying a different value, and no data to return - thus it should be the default of the column, which in case of a NULL column (e.g. a col that can be NULL) with no other DEFAULT value specified in the schema, is NULL.
> 
> 
>> SELECT * FROM graph;
>> latch origid destid weight seq linkid
>> NULL 1 2 1 NULL NULL
>> NULL 2 1 1 NULL NULL
>> NULL 1 3 1 NULL NULL
>> NULL 3 1 1 NULL NULL
>> NULL 3 4 1 NULL NULL
>> NULL 4 3 1 NULL NULL
>> NULL 5 6 1 NULL NULL
>> NULL 6 5 1 NULL NULL
>>
>> Same for no latch with a filter:
>>
>> SELECT * FROM graph WHERE destid=2 and origid=1;
>> latch origid destid weight seq linkid
>> NULL 1 2 1 NULL NULL
>>
>>
>>
>>
>> On 29/05/13 08:08, Arjen Lentz wrote:
>>> Hi Andrew
>>>
>>>> what should a no_search latch return?
>>>
>>> For latch=0/no_search, the table should look as inserted (i.e. like
>>> a regular table).
>>>
>>> I was just wondering if you'd also set "no_search" as the default,
>>> but I reckon it might be better to use an empty string or NULL
>>> rather than no_search. Can you change that without causing hassles
>>> elsewhere?
>>>
>>>
>> <snipped>
>>
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>