Re: [HACKERS] Why NESTED LOOP Not Allowed for FULL and RIGHT Join.

[Tom Lane]

"Rushabh Lathia" <[EMAIL PROTECTED]> writes:
> can anyone let me know that why Nested Loop path is not allowed if jointype
> are JOIN_RIGHT or JOIN_FULL?

How are you going to track which of the inner-relation rows never find a
join partner and hence need to be emitted on their own?

regards, tom lane

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[HACKERS] Why NESTED LOOP Not Allowed for FULL and RIGHT Join.

[Rushabh Lathia]

Hi,

can anyone let me know that why Nested Loop path is not allowed if jointype
are JOIN_RIGHT or JOIN_FULL?


At match_unsorted_outer(), we having case where nestjoinOK = false if there
are
JOIN_RIGHT or JOIN_FULL.

match_unsorted_outer()
{

case JOIN_RIGHT:
case JOIN_FULL:
nestjoinOK = false;

..
}

wondering why ?

Regards,
Rushabh Lathia

[EMAIL PROTECTED]