🚀 go-pugleaf

U�ytkownik "Wayne Niddery [TeamB]" <wniddery@chaffaci.on.ca> napisa� w 
wiadomo�ci news:46ee8f07@newsgroups.borland.com...
> Karol Bieniaszewski wrote:
>>
>>> I would try this:
>>>
>>> FROM
>>> TABLE_C C
>>> INNER JOIN TABLE_A A ON A.ID=C.ID_OBJ
>>> INNER JOIN TABLE_B B ON B.ID_OBJ=C.ID_OBJ AND B.SYSTEM=C.SYSTEM
>>> LEFT JOIN TABLE_D D ON D.NAZWA=C.ALARM
>>> WHERE
>>> C.ZRODLO=:PARAM_X
>>> AND B.KOD=:PARAM_Y
>>> AND B.SYSTEM=:PARAM_Z
>>
>> now plan is :(
>> PLAN JOIN (JOIN (A NATURAL,C INDEX (IXA_TABLE_C__OBJ__ZRO__SYS),B
>> INDEX (IXA_TABLE_B__KOD__SYSTEM, FK_TABLE_B__ID_OBJ)),D INDEX
>> (IXAU__TABLE_D__NAZWA))
>
> You could try making A a left join. If there is always a match, the result 
> set will be the same, if there could be C's without a matching A then add 
> a condition to the where clause : ' A.ID is not null'.
>

this does not change anything
in last query

but do the trick (left join) in query like this

SELECT
*
FROM
TABLE_B B
LEFT JOIN TABLE_A A ON B.ID_OBJ=A.ID
INNER JOIN TABLE_C C  ON C.ID_OBJ=A.ID AND B.SYSTEM=C.SYSTEM AND 
C.ZRODLO=:PARAM_X
LEFT JOIN TABLE_D D ON C.ALARM=D.NAZWA
WHERE
B.KOD=:PARAM_Y
AND B.SYSTEM=:PARAM_Z

PLAN JOIN (JOIN (JOIN (B INDEX (IXA_OBIEKTST_DB__KOD__SYSTEM),A INDEX 
(PK_ADRESY_DB__ID)),C INDEX (IXA_ELEMSTAN_DB__OBJ__ZRO__SYS)),SA INDEX 
(IXAU__SLAL_DB__NAZWA))


greate thanks
Karol Bieniaszewski