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> >> >> -- >> Mailing list: https://launchpad.net/~oqgraph-dev >> Post to : oqgraph-dev@lists.launchpad.net >> Unsubscribe : https://launchpad.net/~oqgraph-dev >> More help : https://help.launchpad.net/ListHelp > -- Mailing list: https://launchpad.net/~oqgraph-dev Post to : oqgraph-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~oqgraph-dev More help : https://help.launchpad.net/ListHelp
