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Re: which is best for JOIN approach
Posted by: Ra Nala
Date: November 25, 2015 02:42AM

Øystein Grøvlen Wrote:
-------------------------------------------------------
> Hi,
>
> I assume that you have indexes on all your id
> columns.
>
Yes Sir, i have indexes on mentioned columns
> For the second alternative, the join order is
> given: a -> b -> ec
>
> For the first alternative, both the join order
> above and a -> ec -> b is possible.
>
> Whether the processing ec before b is beneficial
> depends on the size of the tables, and the number
> of matching ids in the two tables.
>
I have 5000000 records in ec table as well on other tables, that's why i am thinking about best JOIN approach.

> In other words, I would choose the first
> alternative because it gives the Query Optimizer
> more alternatives to evaluate.

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