Re: Learning EXPLAIN

Ah, I see now that the article you linked to in the OP is written by the
same author and is maybe the very same content. If so, that sure seems
pretty comprehensive to me, though I've also been reading this list, off
and on, for many years, which has probably filled a lot of the gaps left by
the original blog posts.

On Fri, Dec 8, 2017 at 8:47 PM, Sam Gendler <sgendler(at)ideasculptor(dot)com>
wrote:

> What about the many-part explanation posted on the blog that accompanies
> explain.depesz.com. Here is the first installment. I seem to remember
> that there are 5 or 6 installments.
>
> https://www.depesz.com/2013/04/16/explaining-the-unexplainable/
>
> On Fri, Dec 8, 2017 at 8:44 AM, Gustavo Velasquez <gustavojunior(at)gmail(dot)com
> > wrote:
>
>> Dude,
>>
>> You can rest assured that at least the Brazilians members will always
>> know based on your last name you are not the same :-).
>>
>> What's the point of explaining that anyways? Got curious.
>>
>> As to what pertains to the topic:
>>
>> This is another simple yet effective doc:
>>
>> https://wiki.postgresql.org/images/4/45/Explaining_EXPLAIN.pdf
>>
>> Execution plans are tricky and reading them accurately to make good
>> decisions require a lot of experience and awareness of the situation. It
>> does not only require that you know how to read the tool itself but also
>> know how the DB and schemas have been designed, if stats are up to date,
>> how tables are populated, frequency and type of queries, adequate indexing
>> in place, the hardware it sits on, etc.
>>
>> It's a mix of science, broaden knowledge, perspicacity, and why not
>> say, it's an art.
>>
>> Have a great weekend.
>>
>> ____________________________________________________________
>> _______________
>> Gustavo Velasquez
>> +1 (256) 653-9725 <(256)%20653-9725>
>>
>>
>> On Fri, Dec 8, 2017 at 7:32 AM, Flavio Henrique Araque Gurgel <
>> fhagur(at)gmail(dot)com> wrote:
>>
>>>
>>> Em sex, 8 de dez de 2017 às 14:20, Guillaume Lelarge <
>>> guillaume(at)lelarge(dot)info> escreveu:
>>>
>>>> Hi,
>>>>
>>>> 2017-12-08 2:12 GMT+01:00 Flávio Henrique <yoshimit(at)gmail(dot)com>:
>>>>
>>>>> Hi experts!
>>>>>
>>>>> I read this nice article about Understanding EXPLAIN [1] weeks ago
>>>>> that opened my mind about the tool, but it seems no enough to explain a lot
>>>>> of plans that I see in this list.
>>>>>
>>>>
>>>> Thanks.
>>>>
>>>> I often read responses to a plan that are not covered by the article.
>>>>>
>>>>> I need/want to know EXPLAIN better.
>>>>>
>>>>> Can you kindly advise me a good reading about advanced EXPLAIN?
>>>>>
>>>>>
>>>> There's not much out there. This document was written after reading
>>>> this list, viewing some talks (you may find a lot of them on youtube), and
>>>> reading the code.
>>>>
>>>> I intend to update this document, since I learned quite more since
>>>> 2012. Though I didn't find the time yet :-/
>>>>
>>>> Anyway, thanks.
>>>>
>>>>
>>> Hello all
>>>
>>> I would like to make clear that there are two "Flavio Henrique" on the
>>> lists, me beeing one of them, I'd like to say that I'm not the OP.
>>> A bit off-topic anyway, thanks for understanding.
>>>
>>> Flavio Gurgel
>>>
>>>
>>
>