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Re: Condition pushdown: why (=) is pushed down into join, but BETWEEN or >= is not? - Mailing list pgsql-hackers

From Andy Fan
Subject Re: Condition pushdown: why (=) is pushed down into join, but BETWEEN or >= is not?
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Msg-id CAKU4AWrdeQZ8xvf=DVhndUs=RGn8oVoSJvYK3Yj7uWq2=dt=Mg@mail.gmail.com
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In response to Re: Condition pushdown: why (=) is pushed down into join, but BETWEEN or >= is not?  (Andy Fan <zhihui.fan1213@gmail.com>)
Responses Re: Condition pushdown: why (=) is pushed down into join, but BETWEEN or >= is not?  (Andy Fan <zhihui.fan1213@gmail.com>)
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> Of course, this breaks the estimates in the faster query, because we now
> apply the condition twice - once for the index scan, one as the join
> clause. So instead of ~100k rows the join is estimated as ~1000 rows.

I think my patch has addressed this. Here is the example: ...  
 
So I think knowing what bad it is to have this feature is the key point to discussion now. 



I forgot to upload these patches,  upload them now.  

--
Best Regards
Andy Fan
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