Re: [Proposal] Global temporary tables

so 1. 2. 2020 v 14:39 odesílatel 曾文旌(义从) <wenjing(dot)zwj(at)alibaba-inc(dot)com>
napsal:

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> 2020年1月30日 下午10:21，Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> 写道：
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> čt 30. 1. 2020 v 15:17 odesílatel 曾文旌(义从) <wenjing(dot)zwj(at)alibaba-inc(dot)com>
> napsal:
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>> > 2020年1月29日 下午9:48，Robert Haas <robertmhaas(at)gmail(dot)com> 写道：
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>> > On Tue, Jan 28, 2020 at 12:12 PM 曾文旌(义从) <wenjing(dot)zwj(at)alibaba-inc(dot)com>
>> wrote:
>> >>> Opinion by Pavel
>> >>> + rel->rd_islocaltemp = true; <<<<<<< if this is valid, then the
>> name of field "rd_islocaltemp" is not probably best
>> >>> I renamed rd_islocaltemp
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>> >> I don't see any change?
>> >>
>> >> Rename rd_islocaltemp to rd_istemp in
>> global_temporary_table_v8-pg13.patch
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>> > In view of commit 6919b7e3294702adc39effd16634b2715d04f012, I think
>> > that this has approximately a 0% chance of being acceptable. If you're
>> > setting a field in a way that is inconsistent with the current use of
>> > the field, you're probably doing it wrong, because the field has an
>> > existing purpose to which new code must conform. And if you're not
>> > doing that, then you don't need to rename it.
>> Thank you for pointing it out.
>> I've rolled back the rename.
>> But I still need rd_localtemp to be true, The reason is that
>> 1 GTT The GTT needs to support DML in read-only transactions ,like local
>> temp table.
>> 2 GTT does not need to hold the lock before modifying the index buffer
>> ,also like local temp table.
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>> Please give me feedback.
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> maybe some like
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> rel->rd_globaltemp = true;
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> and somewhere else
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> if (rel->rd_localtemp || rel->rd_globaltemp)
> {
> ...
> }
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> I tried to optimize code in global_temporary_table_v10-pg13.patch
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> Please give me feedback.
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I tested this patch and I have not any objections - from my user
perspective it is work as I expect

+#define RELATION_IS_TEMP(relation) \
+ ((relation)->rd_islocaltemp || \
+ (relation)->rd_rel->relpersistence == RELPERSISTENCE_GLOBAL_TEMP)

It looks little bit unbalanced

maybe is better to inject rd_isglobaltemp to relation structure

and then

it should to like

+#define RELATION_IS_TEMP(relation) \
+ ((relation)->rd_islocaltemp || \
+ (relation)->rd_isglobaltemp))

But I have not idea if it helps in complex

> Wenjing
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>> Wenjing
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>> >
>> > --
>> > Robert Haas
>> > EnterpriseDB: http://www.enterprisedb.com
>> > The Enterprise PostgreSQL Company
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