Horton

Re: [Proposal] Global temporary tables

曾文旌 (义从) <wenjing.zwj@alibaba-inc.com>

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From: 曾文旌 <wenjing.zwj@alibaba-inc.com>
To: Prabhat Sahu <prabhat.sahu@enterprisedb.com>
Cc: Pavel Stehule <pavel.stehule@gmail.com>, tushar <tushar.ahuja@enterprisedb.com>, Robert Haas <robertmhaas@gmail.com>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Konstantin Knizhnik <k.knizhnik@postgrespro.ru>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>, "蔡松露(子嘉)" <zijia@taobao.com>, "Cai, Le" <le.cai@alibaba-inc.com>
Date: 2020-04-29T03:22:42Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. PageAddItemExtended(): Add LP_UNUSED assertion.

  2. Remove temporary files after backend crash

  3. Fix comment in indexing.c

  4. Fix failure to ignore leftover temp tables after a server crash.


> 2020年4月27日 下午9:48，Prabhat Sahu <prabhat.sahu@enterprisedb.com> 写道：
> 
> Thanks Wenjing, for the fix patch for previous issues.
> I have verified the issues, now those fix look good to me.
> But the below error message is confusing(for gtt2).
> 
> postgres=# drop table gtt1;
> ERROR:  cannot drop global temp table gtt1 when other backend attached it.
> 
> postgres=# drop table gtt2;
> ERROR:  cannot drop index idx2 on global temp table gtt2 when other backend attached it.
> 
> I feel the above error message shown for "DROP TABLE gtt2;" is a bit confusing(looks similar to DROP INDEX gtt2;).
> If possible, can we keep the error message simple as "ERROR:  cannot drop global temp table gtt2 when other backend attached it."?
> I mean, without giving extra information for the index attached to that GTT.
Fixed the error message to make the expression more accurate. In v33.


Wenjing



> 
> On Mon, Apr 27, 2020 at 5:34 PM 曾文旌 <wenjing.zwj@alibaba-inc.com <mailto:wenjing.zwj@alibaba-inc.com>> wrote:
> 
> 
>> 2020年4月27日 下午5:26，Prabhat Sahu <prabhat.sahu@enterprisedb.com <mailto:prabhat.sahu@enterprisedb.com>> 写道：
>> 
>> Hi Wenjing,
>> 
>> Please check the below scenario shows different error message with "DROP TABLE gtt;" for gtt with and without index.
>> -- Session1:
>> postgres=# create global temporary table gtt1 (c1 int);
>> CREATE TABLE
>> postgres=# create global temporary table gtt2 (c1 int);
>> CREATE TABLE
>> postgres=# create index idx2 on gtt2(c1);
>> CREATE INDEX
>> 
>> -- Session2:
>> postgres=# drop table gtt1;
>> ERROR:  can not drop relation gtt1 when other backend attached this global temp table
>> postgres=# drop table gtt2;
>> ERROR:  can not drop index gtt2 when other backend attached this global temp table.
> For DROP GTT, we need to drop the index on the table first. 
> So the indexes on the GTT are checked first.
> But the error message needs to be fixed.
> Fixed in v32
> 
> 
> wenjing
> 
> 
> 
> 
>> 
>> -- 
>> With Regards,
>> Prabhat Kumar Sahu
>> EnterpriseDB: http://www.enterprisedb.com <http://www.enterprisedb.com/>
> 
> 
> 
> -- 
> With Regards,
> Prabhat Kumar Sahu
> EnterpriseDB: http://www.enterprisedb.com <http://www.enterprisedb.com/>