Обсуждение: Header meaning for pg_dump
Dear All,
I had open the backup file of PostgreSQL created by pg_dump command. I found that pg_dump make a comment line as header for each module it backup. I try to understand the meaning of value contained on header for my sample header
--
-- TOC entry 1427 (class 1259 OID 1216127)
-- Dependencies: 7
-- Name: t_option; Type: TABLE; Schema: public; Owner: postgres; Tablespace:
--
-- TOC entry 1427 (class 1259 OID 1216127)
-- Dependencies: 7
-- Name: t_option; Type: TABLE; Schema: public; Owner: postgres; Tablespace:
--
Could you please advise me for.... What does they mean? and What the value used for?
Thank You.
NETsolutions Asia Limited
+66 (2) 237 7247
Вложения
Premsun Choltanwanich wrote: > Dear All, > > I had open the backup file of PostgreSQL created by pg_dump command. I found > that pg_dump make a comment line as header for each module it backup. I try to > understand the meaning of value contained on header for my sample header > > -- > -- TOC entry 1427 (class 1259 OID 1216127) > -- Dependencies: 7 > -- Name: t_option; Type: TABLE; Schema: public; Owner: postgres; Tablespace: > -- > Could you please advise me for.... What does they mean? and What the value used > for? I'm not sure that they're used for anything in that form - that's just documenting internal details. TOC - Table Of Contents OID - Object IDentifier - as used by PG to reference tables,functions etc. Dependencies - iirc is the number of references to this table (e.g. foreign keys). The others explain themselves. Check the manual section on system tables, and perhaps try: SELECT OID,* FROM pg_class WHERE relname='t_option' HTH -- Richard Huxton Archonet Ltd
Dear Richard,
Regarding the information you give to me, I understand that this information is a thing that normally used by PostgreSQL system. And the information seem to be placed on a comment area. So, Who need to have a clearly understanding on the header information?
Thank you
>>> Richard Huxton <dev@archonet.com> 11/6/2006 15:41 >>>
Premsun Choltanwanich wrote:
> Dear All,
>
> I had open the backup file of PostgreSQL created by pg_dump command. I found
> that pg_dump make a comment line as header for each module it backup. I try to
> understand the meaning of value contained on header for my sample header
>
> --
> -- TOC entry 1427 (class 1259 OID 1216127)
> -- Dependencies: 7
> -- Name: t_option; Type: TABLE; Schema: public; Owner: postgres; Tablespace:
> --
> Could you please advise me for.... What does they mean? and What the value used
> for?
I'm not sure that they're used for anything in that form - that's just
documenting internal details.
TOC - Table Of Contents
OID - Object IDentifier - as used by PG to reference tables,functions etc.
Dependencies - iirc is the number of references to this table (e.g.
foreign keys).
The others explain themselves.
Check the manual section on system tables, and perhaps try:
SELECT OID,* FROM pg_class WHERE relname='t_option'
HTH
--
Richard Huxton
Archonet Ltd
NETsolutions Asia Limited
+66 (2) 237 7247
Вложения
On Tue, Nov 07, 2006 at 08:40:54AM +0700, Premsun Choltanwanich wrote: > Dear Richard, > > Regarding the information you give to me, I understand that this > information is a thing that normally used by PostgreSQL system. And > the information seem to be placed on a comment area. So, Who need to > have a clearly understanding on the header information? AFAIK nothing (in the main distribution) actually uses it. It's more a header for people while they're scanning the dump. It also makes a nice anchor point for sed scripts if you want to extract a single object from the dump. Have a nice day, -- Martijn van Oosterhout <kleptog@svana.org> http://svana.org/kleptog/ > From each according to his ability. To each according to his ability to litigate.