Обсуждение: uuid for each postgres install?
Hi all. Im wondering if there is, maybe at compilation time, some sort of unique identifier who identifies the actual installation. It would be even better if can be accesed in SQL form. At "initdb" time would be accepted, too. Thanks! Gerardo
On 09/25/2014 01:02 PM, Gerardo Herzig wrote: > Hi all. Im wondering if there is, maybe at compilation time, some sort of unique identifier who identifies the actual installation. > > It would be even better if can be accesed in SQL form. > At "initdb" time would be accepted, too. initdb does create a Database system identifier which can seen using pg_controldata: postgres@killi:~> pg_controldata /usr/local/pgsql/data pg_control version number: 903 Catalog version number: 201008051 Database system identifier: 5861256043884404217 Database cluster state: shut down A quick search showed that folks would like an SQL way of getting this and that none is available as far as I can determine. The only solution I could find was grepping the pg_controldata output. > > > Thanks! > > Gerardo > > -- Adrian Klaver adrian.klaver@aklaver.com
Well, thats are good news. At least its a good starting point. Thanks Adrian! Gerardo ----- Mensaje original ----- > De: "Adrian Klaver" <adrian.klaver@aklaver.com> > Para: pgsql-sql@postgresql.org > Enviados: Jueves, 25 de Septiembre 2014 17:18:17 > Asunto: Re: [SQL] uuid for each postgres install? > > On 09/25/2014 01:02 PM, Gerardo Herzig wrote: > > Hi all. Im wondering if there is, maybe at compilation time, some > > sort of unique identifier who identifies the actual installation. > > > > It would be even better if can be accesed in SQL form. > > At "initdb" time would be accepted, too. > > initdb does create a Database system identifier which can seen using > pg_controldata: > > postgres@killi:~> pg_controldata /usr/local/pgsql/data > pg_control version number: 903 > Catalog version number: 201008051 > Database system identifier: 5861256043884404217 > Database cluster state: shut down > > A quick search showed that folks would like an SQL way of getting > this > and that none is available as far as I can determine. The only > solution > I could find was grepping the pg_controldata output. > > > > > > > Thanks! > > > > Gerardo > > > > > > > -- > Adrian Klaver > adrian.klaver@aklaver.com > > > -- > Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-sql >
2014-09-26 6:56 GMT+09:00 Gerardo Herzig <gherzig@fmed.uba.ar>: > ----- Mensaje original ----- >> De: "Adrian Klaver" <adrian.klaver@aklaver.com> >> Para: pgsql-sql@postgresql.org >> Enviados: Jueves, 25 de Septiembre 2014 17:18:17 >> Asunto: Re: [SQL] uuid for each postgres install? >> >> On 09/25/2014 01:02 PM, Gerardo Herzig wrote: >> > Hi all. Im wondering if there is, maybe at compilation time, some >> > sort of unique identifier who identifies the actual installation. >> > >> > It would be even better if can be accesed in SQL form. >> > At "initdb" time would be accepted, too. >> >> initdb does create a Database system identifier which can seen using >> pg_controldata: >> >> postgres@killi:~> pg_controldata /usr/local/pgsql/data >> pg_control version number: 903 >> Catalog version number: 201008051 >> Database system identifier: 5861256043884404217 >> Database cluster state: shut down >> >> A quick search showed that folks would like an SQL way of getting this >> and that none is available as far as I can determine. The only solution >> I could find was grepping the pg_controldata output. > > Well, thats are good news. At least its a good starting point. > Thanks Adrian! Please note that the database system identifier is generated based on the point in time when initdb was run and is *not* guaranteed to be unique; in the source it's described as a "hopefully-unique system identifier code" [1]. The "uniqueness" has been improved somewhat for 9.4 but as the commit message notes, "this is still hardly guaranteed-universally-unique" [2]. [1] http://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/access/transam/xlog.c;h=46eef5f21bab2bb9cb59ee9f6388c9059bb5499a;hb=HEAD - see function BootStrapXLOG() [2] http://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=5035701e07e8bd395aa878465a102afd7b74e8c3 Regards Ian Barwick PS please don't top-post, it makes people grumpy and the thread harder to read. -- Ian Barwick http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training & Services