join indices

Analytics
Enthusiast

join indices

Suppose, I had a join qry which is using join indices currently. Incase I change the joining column the it might not use join indices. Is there any way to force join indices?

3 REPLIES
Enthusiast

Re: join indices

Hi Sankalp,

I do not beleive that a query can be forced to use join index, as the use of join index is a processing decision made by the optimizer  based on statistics. The only way is to collect the statistcs as required and keep them updated. This way optimizer will be better able ti use index joins in query execution.

Khurram
Enthusiast

Re: join indices

Hi Sankalp,

We make join table for a purpose(s) especially performance to serve business reqt.It can be Join of large table with another one to get only reqd fields, frequently accessed queries etc.

It is all upto the Optimizer even if it tries to use a cover index. Run  your query and see the explain. 

Cheers,

Raja

Enthusiast

Re: join indices

Thanks! Saeed.

Thanks! Raja.