🚀 go-pugleaf

Uzytkownik "Wayne Niddery (TeamB)" <wniddery@chaffaci.on.ca> napisal w 
wiadomosci news:48612e73@newsgroups.borland.com...
> "Karol Bieniaszewski" <liviuslivius@poczta.onet.pl> wrote in message 
> news:4860e8bb$1@newsgroups.borland.com...
>>
>> but if i try
>>
>> select
>> *
>> from
>> XXX B
>> PLAN (B A NATURAL)
>> PLAN(B B NATURAL)
>>
>> i get error "dynamic sql error sql error code = -104 Token unknown .. 
>> PLAN
>>
>> how can i store plan for this type of query???
>
> It is showing you the plans for each view in the query. When trying to 
> specify your own plan, you can only specify *one* as far as I know - for 
> your own query, not the underlying views.
>
> So likely this would be ok:
> select * from
> XXX B
> PLAN (B NATURAL)
>
> However, you really should not be specifying your own plans. In almost all 
> cases a query can be optimized simply by adjusting the structure or by 
> adding appropriate indexes. Using you own plans should be ab absolutely 
> last resort only.
>
> -- 
> Wayne Niddery - TeamB (www.teamb.com)
> Winwright, Inc. (www.winwright.ca)

yes but indexes have wrong calculation of selectivity
if i select something with foreign key
e.g. table have 10000 records and only 90 have value but rest is null
then selectivity is very bad - but almost queries look for this 90 not for 
null
and then plan are in most case NATURAL :(
i suppose that indexes should have two selectivity for "not null" and "with 
null"

now i create selectable stored procedure to fix my problems
views are bad becaouse of plans :/

Karol Bieniaszewski