Horton

Re: [Proposal] Global temporary tables

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

View thread
From: 曾文旌(义从) <wenjing.zwj@alibaba-inc.com>
To: Prabhat Sahu <prabhat.sahu@enterprisedb.com>
Cc: "Robert Haas" <robertmhaas@gmail.com>, "tushar" <tushar.ahuja@enterprisedb.com>, "Pavel Stehule" <pavel.stehule@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>, 萧少聪(铁庵) <shaocong.xsc@alibaba-inc.com>
Date: 2020-03-09T16:28:12Z
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3月9日 下午8:24，Prabhat Sahu <prabhat.sahu@enterprisedb.com> 写道：
> 
> Hi All,
> 
> Kindly check the below scenario.
> 
> Case 1: 
> postgres=# CREATE GLOBAL TEMPORARY TABLE gtt1(c1 int) on commit delete rows;
> CREATE TABLE
> postgres=# CREATE GLOBAL TEMPORARY TABLE gtt2(c1 int) on commit preserve rows;
> CREATE TABLE
> postgres=# vacuum gtt1;
> VACUUM
> postgres=# vacuum gtt2;
> VACUUM
> postgres=# vacuum;
> VACUUM
> postgres=# \q
> 
> Case 2: Exit and reconnect to psql prompt.
> [edb@localhost bin]$ ./psql  postgres 
> psql (13devel)
> Type "help" for help.
> 
> postgres=# vacuum gtt1;
> WARNING:  skipping vacuum empty global temp table "gtt1"
> VACUUM
> postgres=# vacuum gtt2;
> WARNING:  skipping vacuum empty global temp table "gtt2"
> VACUUM
> postgres=# vacuum;
> WARNING:  skipping vacuum empty global temp table "gtt1"
> WARNING:  skipping vacuum empty global temp table "gtt2"
> VACUUM
> 
> Although in "Case1" the gtt1/gtt2 are empty, we are not getting "WARNING:  skipping vacuum empty global temp table" for VACUUM in "Case 1".
> whereas we are getting the "WARNING" for VACUUM in "Case2".
I fixed the warning message, It's more accurate now.

Wenjing



> 
> 
> On Fri, Mar 6, 2020 at 12:41 PM 曾文旌(义从) <wenjing.zwj@alibaba-inc.com <mailto:wenjing.zwj@alibaba-inc.com>> wrote:
> 
> 
> > 2020年3月5日 下午10:38，Robert Haas <robertmhaas@gmail.com <mailto:robertmhaas@gmail.com>> 写道：
> > 
> > On Thu, Mar 5, 2020 at 9:19 AM tushar <tushar.ahuja@enterprisedb.com <mailto:tushar.ahuja@enterprisedb.com>> wrote:
> >> WARNING:  relfilenode 13589/1663/19063 not exist in gtt shared hash when forget
> >> ERROR:  out of shared memory
> >> HINT:  You might need to increase max_active_gtt.
> >> 
> >> also , would be great  if we can make this error message  user friendly like  - "max connection reached"  rather than memory error
> > 
> > That would be nice, but the bigger problem is that the WARNING there
> > looks totally unacceptable. It's looks like it's complaining of some
> > internal issue (i.e. a bug or corruption) and the grammar is poor,
> > too.
> 
> Yes, WARNING should not exist.
> This is a bug in the rollback process and I have fixed it in global_temporary_table_v17-pg13.patch
> 
> 
> Wenjing
> 
> 
> > 
> > -- 
> > Robert Haas
> > EnterpriseDB: http://www.enterprisedb.com <http://www.enterprisedb.com/>
> > The Enterprise PostgreSQL Company
> 
> 
> 
> 
> 
> -- 
> With Regards,
> Prabhat Kumar Sahu
> EnterpriseDB: http://www.enterprisedb.com <http://www.enterprisedb.com/>