Jim Smith wrote:
> In message <4164e5de$0$10351$afc38c87_at_news.optusnet.com.au>, Howard J.
> Rogers <howardjr_at_dizwell.com> writes
>>xtanto wrote:
>>
>>> Hi Gurus,
>>>
>>> I have Table A with PK on a,b,c,d (so I have index on this)
>>> Table A has FK on (a,b) to Table B)
>>>
>>> Table B with PK on a,b
>>>
>>> I have questions :
>>>
>>> (1) On Table A, what queries that can make use of the Index ?
>>>
>>> (2) On Table A, Do I need Index on (a,b) for the FK
>>>
>>> Thanks for your help,
>>> xtanto
>>
>>
>>This is all a bit abstract, isn't it?
>>
>>I'm sure someone here is going to ask when you have to have this homework
>>in by...
>>
>>Besides which, although you might not think it, but the advice in respect
>>of both questions is influenced by Oracle version. But that said:
>>
>>1. Any query. In 9i more than in 8i. Read up on skip scanning, for
>>example. 2. Yes. Even in 9i, if you ever intend to modify table B's
>>primary key.
>>
>
> Does the fact that (a,b) is the leading portion of the primary key have
> not any effect on this?
Can we try being a little more precise? Have an effect on what?
Regards
HJR
Received on Thu Oct 07 2004 - 04:12:46 CDT
