On Mon, Jun 26, 2023 at 1:45 PM Pavel Stehule <pavel.stehule@gmail.com> wrote:
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> po 26. 6. 2023 v 19:43 odesílatel Pavel Stehule <pavel.stehule@gmail.com> napsal:
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>> Hi
>>
>> po 26. 6. 2023 v 19:41 odesílatel James Coleman <jtc331@gmail.com> napsal:
>>>
>>> Hello,
>>>
>>> Have we ever discussed running an analyze immediately after creating a table?
>>>
>>> Consider the following:
>>>
>>> create table stats(i int, t text not null);
>>> explain select * from stats;
>>> Seq Scan on stats (cost=0.00..22.70 rows=1270 width=36
>>> analyze stats;
>>> explain select * from stats;
>>> Seq Scan on stats (cost=0.00..0.00 rows=1 width=36)
>>>
>>> Combined with rapidly increasing error margin on row estimates when
>>> adding joins means that a query joining to a bunch of empty tables
>>> when a database first starts up can result in some pretty wild plan
>>> costs.
>>>
>>> This feels like a simple idea to me, and so I assume people have
>>> considered it before. If so, I'd like to understand why the conclusion
>>> was not to do it, or, alternatively if it's a lack of tuits.
>>
>>
>> I like this. On the second hand, described behaviour is designed for ensuring of back compatibility.
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> if you break this back compatibility, then the immediate ANALYZE is not necessary
I don't follow what backwards compatibility you're referencing. Could
you expand on that?
Regards,
James Coleman