Обсуждение: Re: [BUGS] Where clause in pg_dump: need help
1.- CCing to the list ( remember to hit reply-all or whatever your MUA uses for that, otherwise threads may get lost ). 2.- Try to avoid top-posting, it's not the style of the list ( or mine ). On Fri, Jul 8, 2016 at 4:43 AM, Prashanth Adiyodi <Prashantha@celltick.com> wrote: > Basically my requirement is, I have a live Db with certain tables and a backup Db at another location (both on postgressql).I need to take a backup of this live DB every night for the previous day (i.e the backup script running on 07/07/2016will take the backup of the DB for 06/07/2016). This backup will be then transferred to the backup DB server andwill be inserted into that DB. From what I have read pg_dump is the solution (similar to export in oracle), do you thinkof any other approach to get to this objective, have you come across a script or something that already does this, Your requirement is a bit 'understated'. I assume your problem is: 1.- You have a backup with a series of tables which get inserted WITH a timestamp. 2.- At the end of the day you want to transfer the inserted data, and only the inserted data, to another server and insert it ther. If BOTH servers are postgres, you can do it easily with a series of COPY commands easily. If the target one is not postgres I would use it too, but pass the COPY data through a perl script to generate whatever syntax the target DB needs ( I've done that to go from postgres to sql server and back using freebcp, IIRC, on the sql server side ) You still can have problems IF you have updates to the tables, or deletions, or <insert your favorite problematic operation here>. But if you just have insertions, copy is easy to do. Francisco Olarte.
1.- CCing to the list ( remember to hit reply-all or whatever your MUA
uses for that, otherwise threads may get lost ).
2.- Try to avoid top-posting, it's not the style of the list ( or mine ).
On Fri, Jul 8, 2016 at 4:43 AM, Prashanth Adiyodi
<Prashantha@celltick.com> wrote:
> Basically my requirement is, I have a live Db with certain tables and a backup Db at another location (both on postgressql).
I need to take a backup of this live DB every night for the previous day (i.e the backup script running on 07/07/2016 will take the backup of the DB for 06/07/2016).
This backup will be then transferred to the backup DB server and will be inserted into that DB.
From what I have read pg_dump is the solution (similar to export in oracle), do you think of any other approach to get to this objective, have you come across a script or something that already does this,
psql -c "COPY (SELECT .. WHERE..) TO stdout" | psql -c "COPY (mytable) FROM stdin"
Setup replication and have a scheduled script to set recovery_target_time and puase_at_recovery_target to effectively replicate changes from one DB to other DB and maintaining a gap. But then the targetDB would be a read only replica and needs to be exactly same at the main DB/sourceDB
Your requirement is a bit 'understated'. I assume your problem is:
1.- You have a backup with a series of tables which get inserted WITH
a timestamp.
2.- At the end of the day you want to transfer the inserted data, and
only the inserted data, to another server and insert it ther.
If BOTH servers are postgres, you can do it easily with a series of
COPY commands easily. If the target one is not postgres I would use it
too, but pass the COPY data through a perl script to generate whatever
syntax the target DB needs ( I've done that to go from postgres to sql
server and back using freebcp, IIRC, on the sql server side )
You still can have problems IF you have updates to the tables, or
deletions, or <insert your favorite problematic operation here>. But
if you just have insertions, copy is easy to do.
Francisco Olarte.
--
Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general
101 Cecil Street, #11-11 Tong Eng Building, Singapore 069 533
T: +65 6438 3504 | M: +65 8110 0350 | www.ashnik.com
Hi Sameer, Please see comments inline
Prashanth Adiyodi
Technical Account Manager
Skype: prashanth.adiyodi
Mob: +91-9819488395
From: Sameer Kumar [mailto:sameer.kumar@ashnik.com]
Sent: Friday, July 08, 2016 3:18 PM
To: Francisco Olarte; Prashanth Adiyodi
Cc: pgsql-general@postgresql.org
Subject: Re: [GENERAL] [BUGS] Where clause in pg_dump: need help
On Fri, Jul 8, 2016 at 5:38 PM Francisco Olarte <folarte@peoplecall.com> wrote:
1.- CCing to the list ( remember to hit reply-all or whatever your MUA
uses for that, otherwise threads may get lost ).
2.- Try to avoid top-posting, it's not the style of the list ( or mine ).
On Fri, Jul 8, 2016 at 4:43 AM, Prashanth Adiyodi
<Prashantha@celltick.com> wrote:
> Basically my requirement is, I have a live Db with certain tables and a backup Db at another location (both on postgressql).
Both databases are PostgreSQL (?). What version?
Yes, Both are postgres SQL, ver 9.3.4
I need to take a backup of this live DB every night for the previous day (i.e the backup script running on 07/07/2016 will take the backup of the DB for 06/07/2016).
Does this need to be done for one table or multiple tables?
Multiple tables
This backup will be then transferred to the backup DB server and will be inserted into that DB.
What will you be doing on the target database? Is it a read-only database?
It is not a read only database
From what I have read pg_dump is the solution (similar to export in oracle), do you think of any other approach to get to this objective, have you come across a script or something that already does this,
May be you can use
psql -c "COPY (SELECT .. WHERE..) TO stdout" | psql -c "COPY (mytable) FROM stdin"
OR
Setup replication and have a scheduled script to set recovery_target_time and puase_at_recovery_target to effectively replicate changes from one DB to other DB and maintaining a gap. But then the targetDB would be a read only replica and needs to be exactly same at the main DB/sourceDB
You need to explain more on version of the database, what exactly you aim at doing with the target DB.
Hi, the requirement is this, I have multiple tables where there may not be a timestamp column. I need to run a script which will execute post-midnight say at 2 AM and create a dump file (say data.sql), which will have records for all the previous day. I will then transfer this file to the target server and dump this data there, the idea is to create two copies of the data in case of a disaster on the original database server.
Your requirement is a bit 'understated'. I assume your problem is:
1.- You have a backup with a series of tables which get inserted WITH
a timestamp.
2.- At the end of the day you want to transfer the inserted data, and
only the inserted data, to another server and insert it ther.
If BOTH servers are postgres, you can do it easily with a series of
COPY commands easily. If the target one is not postgres I would use it
too, but pass the COPY data through a perl script to generate whatever
syntax the target DB needs ( I've done that to go from postgres to sql
server and back using freebcp, IIRC, on the sql server side )
You still can have problems IF you have updates to the tables, or
deletions, or <insert your favorite problematic operation here>. But
if you just have insertions, copy is easy to do.
Francisco Olarte.
--
Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general--
--
Best Regards
Sameer Kumar | DB Solution Architect
ASHNIK PTE. LTD.
101 Cecil Street, #11-11 Tong Eng Building, Singapore 069 533
T: +65 6438 3504 | M: +65 8110 0350 | www.ashnik.com
101 Cecil Street, #11-11 Tong Eng Building, Singapore 069 533
T: +65 6438 3504 | M: +65 8110 0350 | www.ashnik.com
Вложения
Hi Sameer, Please see comments inline
Prashanth Adiyodi
Technical Account Manager
Skype: prashanth.adiyodi
Mob: +91-9819488395
From: Sameer Kumar [mailto:sameer.kumar@ashnik.com]
Sent: Friday, July 08, 2016 3:18 PM
To: Francisco Olarte; Prashanth Adiyodi
Cc: pgsql-general@postgresql.org
Subject: Re: [GENERAL] [BUGS] Where clause in pg_dump: need help
On Fri, Jul 8, 2016 at 5:38 PM Francisco Olarte <folarte@peoplecall.com> wrote:
1.- CCing to the list ( remember to hit reply-all or whatever your MUA
uses for that, otherwise threads may get lost ).
2.- Try to avoid top-posting, it's not the style of the list ( or mine ).
On Fri, Jul 8, 2016 at 4:43 AM, Prashanth Adiyodi
<Prashantha@celltick.com> wrote:
> Basically my requirement is, I have a live Db with certain tables and a backup Db at another location (both on postgressql).
Both databases are PostgreSQL (?). What version?
Yes, Both are postgres SQL, ver 9.3.4
I need to take a backup of this live DB every night for the previous day (i.e the backup script running on 07/07/2016 will take the backup of the DB for 06/07/2016).
Does this need to be done for one table or multiple tables?
Multiple tables
This backup will be then transferred to the backup DB server and will be inserted into that DB.
What will you be doing on the target database? Is it a read-only database?
It is not a read only database
From what I have read pg_dump is the solution (similar to export in oracle), do you think of any other approach to get to this objective, have you come across a script or something that already does this,
May be you can use
psql -c "COPY (SELECT .. WHERE..) TO stdout" | psql -c "COPY (mytable) FROM stdin"
OR
Setup replication and have a scheduled script to set recovery_target_time and puase_at_recovery_target to effectively replicate changes from one DB to other DB and maintaining a gap. But then the targetDB would be a read only replica and needs to be exactly same at the main DB/sourceDB
You need to explain more on version of the database, what exactly you aim at doing with the target DB.
Hi, the requirement is this, I have multiple tables where there may not be a timestamp column. I need to run a script which will execute post-midnight say at 2 AM and create a dump file (say data.sql), which will have records for all the previous day. I will then transfer this file to the target server and dump this data there, the idea is to create two copies of the data in case of a disaster on the original database server.
Your requirement is a bit 'understated'. I assume your problem is:
1.- You have a backup with a series of tables which get inserted WITH
a timestamp.
2.- At the end of the day you want to transfer the inserted data, and
only the inserted data, to another server and insert it ther.
If BOTH servers are postgres, you can do it easily with a series of
COPY commands easily. If the target one is not postgres I would use it
too, but pass the COPY data through a perl script to generate whatever
syntax the target DB needs ( I've done that to go from postgres to sql
server and back using freebcp, IIRC, on the sql server side )
You still can have problems IF you have updates to the tables, or
deletions, or <insert your favorite problematic operation here>. But
if you just have insertions, copy is easy to do.
Francisco Olarte.
--
Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general
--
--
Best Regards
Sameer Kumar | DB Solution Architect
ASHNIK PTE. LTD.
101 Cecil Street, #11-11 Tong Eng Building, Singapore 069 533
T: +65 6438 3504 | M: +65 8110 0350 | www.ashnik.com
Вложения
Hi Franciso, My comments below inline -----Original Message----- From: Francisco Olarte [mailto:folarte@peoplecall.com] Sent: Friday, July 08, 2016 3:07 PM To: Prashanth Adiyodi Cc: pgsql-general@postgresql.org Subject: Re: [BUGS] Where clause in pg_dump: need help 1.- CCing to the list ( remember to hit reply-all or whatever your MUA uses for that, otherwise threads may get lost ). 2.- Try to avoid top-posting, it's not the style of the list ( or mine ). On Fri, Jul 8, 2016 at 4:43 AM, Prashanth Adiyodi <Prashantha@celltick.com> wrote: > Basically my requirement is, I have a live Db with certain tables and > a backup Db at another location (both on postgressql). I need to take > a backup of this live DB every night for the previous day (i.e the > backup script running on 07/07/2016 will take the backup of the DB for > 06/07/2016). This backup will be then transferred to the backup DB > server and will be inserted into that DB. From what I have read > pg_dump is the solution (similar to export in oracle), do you think of > any other approach to get to this objective, have you come across a > script or something that already does this, Your requirement is a bit 'understated'. I assume your problem is: 1.- You have a backup with a series of tables which get inserted WITH a timestamp. Adi-The series of tables may or may not have timestamp 2.- At the end of the day you want to transfer the inserted data, and only the inserted data, to another server and insertit ther. Adi-Exactly., somewhere post midnight I need to transfer the inserted data for the day to another DB. If BOTH servers are postgres, you can do it easily with a series of COPY commands easily. If the target one is not postgresI would use it too, but pass the COPY data through a perl script to generate whatever syntax the target DB needs( I've done that to go from postgres to sql server and back using freebcp, IIRC, on the sql server side ) You still can have problems IF you have updates to the tables, or deletions, or <insert your favorite problematic operationhere>. But if you just have insertions, copy is easy to do. Adi- I am OK with the copy command, however I am not able to understand (my bad, I am not used to postgres and using for the 1sttime) the where clause that should be used to achieve this result. I tries using something like the below, psql -d my_db -c 'copy (select * from mytab WHERE date_trunc('day',NOW() - interval '1 day') TO STDOUT' -o data1.copy; but this, I am sure has some syntax errors, could you help correct this, Francisco Olarte.
1.- You have a backup with a series of tables which get inserted WITH a timestamp.
Adi-The series of tables may or may not have timestamp
Hi Adi: ( Is this correct? Adi is what your message uses to mark your replies ). On Sun, Jul 10, 2016 at 6:53 PM, Prashanth Adiyodi <Prashantha@celltick.com> wrote: > Hi Franciso, My comments below inline Got them. Only problem is your MUA does not signal quotes. It looks like some kind of outlook by the headers it sends, so I assume it is normal, I will try to correct it. >> 1.- You have a backup with a series of tables which get inserted WITH a timestamp. > Adi-The series of tables may or may not have timestamp >> 2.- At the end of the day you want to transfer the inserted data, and only the inserted data, to another server and insertit ther. > Adi-Exactly., somewhere post midnight I need to transfer the inserted data for the day to another DB. Then you NEED some kind of marker. The tables WITHOUT timestamp ( point 1 above ) are going to be difficult. For the discussion I assume you are somehow capable of making a SELECT query which identifies inserted data for the day, and that either you do not care about updates/deletions ( not having any is a subset of this condition ) or you can do a query for those too. > Adi- I am OK with the copy command, however I am not able to understand (my bad, I am not used to postgres and using forthe 1st time) the where clause that should be used to achieve this result. Well, then your problem is on the queries. You need to be able to identify the data inserted yesterday. There is no magic way to do it. You NEED some kind of timestamp column. If you lack this you can use a trigger to mark them into auxiliary tables or, if you feel adventurous, you can try to use the xmin/xmax columns ( I would NOT recommend even trying that, given you are having problems with simple select queries ). > I tries using something like the below, > psql -d my_db -c 'copy (select * from mytab WHERE date_trunc('day',NOW() - interval '1 day') TO STDOUT' -o data1.copy; Your where expresion is a constant of timestamp type, i.e., '2016-07-11 12:00:00+00', where needs a BOOLEAN. YOU need to be able to identify the inserted rows. YOU know your data definitions. Ar you able to query them ? > but this, I am sure has some syntax errors, could you help correct this, NOT, because I do not know the table structure. Only you can do that. Francisco Olarte.