| From: | "Scott Marlowe" <scott(dot)marlowe(at)gmail(dot)com> |
|---|---|
| To: | "Gregory Stark" <stark(at)enterprisedb(dot)com> |
| Cc: | Justin <justin(at)emproshunts(dot)com>, pgsql-performance(at)postgresql(dot)org |
| Subject: | Re: getting estimated cost to agree with actual |
| Date: | 2008-06-03 03:06:20 |
| Message-ID: | dcc563d10806022006j3a1dc999t50039d0c9f74caff@mail.gmail.com |
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| Lists: | pgsql-performance |
On Mon, Jun 2, 2008 at 7:20 PM, Gregory Stark <stark(at)enterprisedb(dot)com> wrote:
> "Scott Marlowe" <scott(dot)marlowe(at)gmail(dot)com> writes:
>
>> On Mon, Jun 2, 2008 at 3:43 PM, Justin <justin(at)emproshunts(dot)com> wrote:
>>>
>>> I have noticed that estimated Cost to do the query is way off from Actual.
>>
>> Well, they're not measured in the same units. estimated costs are in
>> terms of the cost to sequentially scan a single tuple, while actual
>> costs are in milliseconds.
>
> s/tuple/page/
Dangit! I knew that too. time for some sleep I guess. :)
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